Glacier Northwest, Inc. v. Teamsters

P R E L I M I N A R Y P R I N T
Volume 598 U. S. Part 2
Pages 771–815
OFFICIAL REPORTS
OF
T H E S U P R E M E C O U R T
June 1, 2023
REBECCA A. WOMELDORF
reporter of decisions
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the bound volume is published. Users are requested to notify the Reporter
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OCTOBER
TERM, 2022
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Syllabus
GLACIER NORTHWEST, INC., dba CALPORTLAND v.
INTERNA
TIONAL BROTHERHOOD OF TEAMSTERS
LOCAL UNION NO. 174
certiorari to the supreme court of washington
No. 21–1449. Argued January 10, 2023—Decided June 1, 2023
Glacier Northwest delivers concrete to customers in Washington State
using ready-mix trucks with rotating drums that prevent the concrete
from hardening during transit. Concrete is highly perishable, and even
concrete in a rotating drum will eventually harden, causing signifcant
damage to the vehicle. Glacier's truck drivers are members of the In-
ternational Brotherhood of Teamsters Local Union No. 174. After a
collective-bargaining agreement between Glacier and the Union expired,
the Union called for a work stoppage on a morning it knew the company
was in the midst of mixing substantial amounts of concrete, loading
batches into ready-mix trucks, and making deliveries. The Union di-
rected drivers to ignore Glacier's instructions to fnish deliveries in
progress. At least 16 drivers who had already set out for deliveries
returned with fully loaded trucks. By initiating emergency maneuvers
to offoad the concrete, Glacier prevented signifcant damage to its
trucks, but all the concrete mixed that day hardened and became
useless.
Glacier sued the Union for damages in state court, claiming that the
Union intentionally destroyed the company's concrete and that this con-
duct amounted to common-law conversion and trespass to chattels. The
Union moved to dismiss Glacier's tort claims on the ground that the
National Labor Relations Act (NLRA) preempted them. While a fed-
eral law generally preempts state law when the two confict, the NLRA
preempts state law even when the two only arguably confict. San
Diego Building Trades Council v. Garmon, 359 U. S. 236, 245. In the
Union's view, the NLRA—which protects employees' rights “to self-
organization, to form, join, or assist labor organizations, . . . and to
engage in other concerted activities for the purpose of collective bar-
gaining or other mutual aid or protection,” 29 U. S. C. § 157—at least
arguably protected the drivers' conduct, so the State lacked the power
to hold the Union accountable for any of the strike's consequences. The
Washington Supreme Court agreed with the Union, reasoning that “the
NLRA preempts Glacier's tort claims related to the loss of its concrete
product because that loss was incidental to a strike arguably protected
by federal law.”

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Held: The NLRA did not preempt Glacier's tort claims alleging that the
U
nion intentionally destroyed the company's property during a labor
dispute. Pp. 779–785.
(a) The parties agree that the NLRA protects the right to strike but
that this right is not absolute. The National Labor Relations Board
has long taken the position—which the parties accept—that the NLRA
does not shield strikers who fail to take “reasonable precautions” to
protect their employer's property from foreseeable, aggravated, and im-
minent danger due to the sudden cessation of work. Bethany Medical
Center, 328 N. L. R. B. 1094. Given this undisputed limitation on the
right to strike, the Court concludes that the Union has not met its bur-
den as the party asserting preemption to demonstrate that the NLRA
arguably protects the drivers' conduct. Longshoremen v. Davis, 476
U. S. 380, 395. Accepting the complaint's allegations as true, the Union
did not take reasonable precautions to protect Glacier's property from
imminent danger resulting from the drivers' sudden cessation of work.
The Union knew that concrete is highly perishable, that it can last for
only a limited time in a delivery truck's rotating drum, and that concrete
left to harden in a truck's drum causes signifcant damage to the truck.
The Union nevertheless coordinated with truck drivers to initiate the
strike when Glacier was in the midst of batching large quantities of
concrete and delivering it to customers. The resulting risk of harm to
Glacier's equipment and destruction of its concrete were both foresee-
able and serious. The Union thus failed to “take reasonable precau-
tions to protect” against this foreseeable and imminent danger. Beth-
any Medical Center, 328 N. L. R. B., at 1094. Indeed, far from taking
reasonable precautions, the Union executed the strike in a manner de-
signed to achieve those results. Because such conduct is not arguably
protected by the NLRA, the state court erred in dismissing Glacier's
tort claims as preempted. Pp. 779–782.
(b) The Union's efforts to resist the conclusion that the NLRA does
not arguably protect its conduct are unavailing. First, the Union em-
phasizes that the NLRA's protection of the right to strike should be
interpreted generously. But the protected right to strike is not abso-
lute, thus the Court must analyze whether the strike exceeded the limits
of conduct protected by the statute.
Second, the Union argues that workers do not forfeit the NLRA's
protections simply by commencing a work stoppage when the loss of
perishable products is foreseeable, but this case involves much more
than that. Given the lifespan of wet concrete, Glacier could not batch
it until a truck was ready to take it. By reporting for duty and pre-
tending as if they would deliver the concrete, the drivers prompted the

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773
Syllabus
creation of the perishable product. Then, they waited to walk off the
job
until the concrete was mixed and poured in the trucks. In so doing,
they not only destroyed the concrete but also put Glacier's trucks in
harm's way.
Third, the Court acknowledges that the Union's decision to initiate
the strike during the workday and failure to give Glacier specifc notice
do not themselves render the Union's conduct unprotected. Still, these
actions are relevant considerations in evaluating whether strikers took
reasonable precautions, whether harm to property was imminent, and
whether that danger was foreseeable. See International Protective
Services, Inc., 339 N. L. R. B. 701, 702–703. Here, the Union's choice
to call a strike after its drivers had loaded a large amount of wet con-
crete into Glacier's delivery trucks strongly suggests that it failed to
take reasonable precautions to avoid foreseeable, aggravated, and immi-
nent harm to Glacier's property.
Finally, while the Union maintains that the drivers took some steps
to protect the trucks, the Union concedes that the NLRA does not argu-
ably protect its actions if those actions posed a material risk of harm to
the trucks. Given that Glacier alleges that the Union took affrmative
steps to endanger Glacier's property rather than reasonable precautions
to mitigate that risk, the NLRA does not arguably protect the Union's
conduct. Pp. 782–784.
198 Wash. 2d 768, 500 P. 3d 119, reversed and remanded.
Barrett, J., delivered the opinion of the Court, in which Roberts,
C. J., and Sotomayor, Kagan, and Kavanaugh, JJ., joined. Thomas, J.,
fled an opinion concurring in the judgment, in which Gorsuch, J., joined,
post, p. 785. Alito, J., fled an opinion concurring in the judgment, in
which Thomas and Gorsuch, JJ., joined, post, p. 788. Jackson, J., fled
a dissenting opinion, post, p. 789.
Noel J. Francisco argued the cause for petitioner. With
him on the briefs were Anthony J. Dick and Matthew J.
Rubenstein.
Vivek Suri argued the cause for the United States as ami-
cus curiae urging reversal. With him on the brief were
So l i c i t o r Gene ra l Prel ogar, De pu ty So l i ci t o r Gene ral
Kneedler, Jennifer A. Abruzzo, Nancy E. Kessler Platt,
Ru th E. Burd i ck, Da v i d Haben stre i t, and Daw n L.
Goldstein.
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Darin M. Dalmat argued the cause for respondent. With
h
im on the brief were Dmitri Iglitzin, Kathleen Phair Bar-
nard, Ben Berger, Easha Anand, and Pamela S. Karlan.*
Justice Barrett delivered the opinion of the Court.
Glacier Northwest, a concrete company, depends on its
truck drivers to deliver concrete to customers in a timely
manner. But when relations between Glacier and its drivers
soured, the drivers went on strike. Their labor union alleg-
edly designed the strike with the intent to sabotage Glacier's
*Briefs of amici curiae urging reversal were fled for the Buckeye Insti-
tute by Jay R. Carson, Robert Alt, and David C. Tryon; for the Chamber
of Commerce of the United States of America by Carter G. Phillips; for
the Coalition for a Democratic Workplace by Steven P. Lehotsky, Adam
Steene, and Andrew B. Davis; for the Landmark Legal Foundation by Mat-
thew C. Forys, Michael J. O'Neill, and Richard P. Hutchison; and for the
National Right to Work Legal Defense Foundation, Inc., by Glenn M.
Taubman and Alyssa K. Hazelwood.
Briefs of amici curiae urging affrmance were fled for the State of
Washington et al. by Robert W. Ferguson, Attorney General of Washing-
ton, Noah G. Purcell, Solicitor General, Peter B. Gonick, Deputy Solicitor
General, and Kate S. Worthington, Assistant Attorney General, and by
the Attorneys General for their respective jurisdictions as follows: Philip
J. Weiser of Colorado, William Tong of Connecticut, Karl A. Racine of the
District of Columbia, Kwame Raoul of Illinois, Aaron M. Frey of Maine,
Maura Healey of Massachusetts, Dana Nessel of Michigan, Keith Ellison
of Minnesota, Aaron D. Ford of Nevada, Matthew J. Platkin of New Jer-
sey, Letitia James of New York, Ellen F. Rosenblum of Oregon, Josh
Shapiro of Pennsylvania, Peter F. Neronha of Rhode Island, and Josh Kaul
of Wisconsin; for Administrative Law Professors et al. by Stacey M. Ley-
ton; for the American Federation of Labor and Congress of Industrial
Organizations by Harold C. Becker and James B. Coppess; for the Consti-
tutional Accountability Center by Elizabeth B. Wydra and Brianne J.
Gorod; for Tort Scholars by John R. Mooney, Aaron Streepy, and Mark
Geistfeld and Sheila L. Birnbaum, both pro se; for Unite Here Interna-
tional et al. by Richard G. McCracken and Paul L. More; for the United
Brotherhood of Carpenters and Joiners of American et al. by David C.
Frederick, Scott K. Attaway Matthew F. Capece, Daniel M. Shanley, and
Nicole G. Berner; and for Matthew Bodie et al. by Jacob Karabell, and
Charlotte Garden and Catherine Fisk, both pro se.
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Opinion of the Court
property. Although Glacier managed to avoid damage to its
del
ivery trucks by deploying emergency maneuvers, the con-
crete that it had already produced that day went to waste.
Glacier sued the union in state court for destroying its
property. But the company did not get very far: The state
court dismissed Glacier's tort claims on the ground that they
were preempted by the National Labor Relations Act. We
reverse.
I
A
Enac ted i n 1935, the Nati ona l Labor Relati ons Ac t
(NLRA) “encourag[es] the practice and procedure of col-
lective bargaining ” between labor and management to re-
solve “industrial disputes arising out of differences as to
wages, hours, or other working conditions.” 49 Stat. 449, 29
U. S. C. § 151. Section 7 of the NLRA protects employees'
rights “to self-organization, to form, join, or assist labor or-
ganizations, to bargain collectively through representatives
of their own choosing, and to engage in other concerted activ-
ities for the purpose of collective bargaining or other mutual
aid or protection.” § 157. Section 8, in turn, prohibits em-
ployers and unions from engaging in certain “unfair labor
practice[s],” such as interfering with employees' exercise of
their § 7 rights. §§ 158(a), (b).
To enforce the NLRA, Congress created the National
Labor Relations Board. The Board is authorized “to pre-
vent any person from engaging in any unfair labor practice”
that “affect[s] commerce.” § 160(a). Its authority kicks in
when a person fles a charge with the agency alleging that
an unfair labor practice is afoot. 29 CFR § 101.2 (2021).
Agency staff investigate the charge, and if it “appears to
have merit,” the agency issues a complaint against the of-
fending party. §§ 101.4, 101.8. After taking evidence and
conducting a hearing, the Board makes the fnal call. 29
U. S. C. §§ 160(b), (c); see also 29 CFR §§ 101.10–101.12. If
it determines that a party has engaged in an unfair labor
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practice, the Board orders it to “cease and desist” from that
prac
tice. 29 U. S. C. § 160(c). The Board may seek enforce-
ment of its order in a federal court of appeals. § 160(e).
And a party aggrieved by the order may ask the court to set
it aside. § 160(f ).
B
Sometimes a party to a labor dispute goes directly to a
court—raising the specter that state law will say one thing
about the conduct underlying the dispute while the NLRA
says another. It is a bedrock rule, of course, that federal
law preempts state law when the two confict. U. S. Const.,
Art. VI, cl. 2. Preemption under the NLRA is unusual,
though, because our precedent maintains that the NLRA
preempts state law even when the two only arguably con-
fict. San Diego Building Trades Council v. Garmon, 359
U. S. 236, 245 (1959) (“When an activity is arguably subject
to § 7 or § 8 of the [NLRA], the States as well as the federal
courts must defer to the exclusive competence of the Na-
tional Labor Relations Board”). This doctrine—named Gar-
mon preemption after the case that originated it—thus goes
beyond the usual preemption rule. Under Garmon, States
cannot regulate conduct “that the NLRA protects, prohibits,
or arguably protects or prohibits.” Wisconsin Dept. of In-
dustry v. Gould Inc., 475 U. S. 282, 286 (1986).
Though broad, this standard has teeth. Longshoremen v.
Davis, 476 U. S. 380, 394 (1986) (“The precondition for pre-
emption, that the conduct be `arguably' protected or prohib-
ited, is not without substance”). It requires more than “a
conclusory assertion” that the NLRA arguably protects or
prohibits conduct. Ibid. “[A] party asserting pre-emption
must advance an interpretation of the [NLRA] that is not
plainly contrary to its language and that has not been `au-
thoritatively rejected' by the courts or the Board.” Id.,
at 395. The party must then “put forth enough evidence
to enable the court to fnd that the Board reasonably could
uphold a claim based on such an interpretation.” Ibid.
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777
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If the court determines that the party has met its burden
to
show that “there is an arguable case for pre-emption,” it
generally must grant the party's preemption defense and
await the Board's resolution of the legal status of the rele-
vant conduct. Id., at 397.
1
After that, “only if the Board
decides that the conduct is not protected or prohibited [by
the NLRA] may the court entertain the litigation.” Ibid.
“[W]hen properly invoked,” Garmon thus “tells us not just
what law applies (federal law, not state law) but who applies
it (the National Labor Relations Board, not the state courts
or federal district courts).” Trollinger v. Tyson Foods, Inc.,
370 F. 3d 602, 608 (CA6 2004).
C
We relay the facts as alleged in the complaint. Glacier
Northwest sells ready-mix concrete to customers in Wash-
ington State. Each batch must be mixed to the customer's
specifications. Af ter Glacier combines the raw ingredi-
ents—cement, sand, aggregate, admixture, and water—in a
hopper, it transfers the resulting concrete to one of its trucks
for prompt delivery.
In this business, time is of the essence. Concrete is
highly perishable—it begins to harden immediately once at
rest. Ready-mix trucks can preserve concrete in a rotating
1
We have recognized exceptions to this rule. One allows a court to
resolve a claim if the party raising it lacks a “reasonable opportunity” to
secure a Board decision on the legal status of the conduct at issue. Sears,
Roebuck & Co. v. Carpenters, 436 U. S. 180, 201 (1978); see also Davis, 476
U. S., at 393, n. 10. Another applies if the conduct in question is “a merely
peripheral concern” of the NLRA. San Diego Building Trades Council
v. Garmon, 359 U. S. 236, 243 (1959). A third covers situations “where
the regulated conduct touche[s] interests so deeply rooted in local feeling
and responsibility that, in the absence of compelling congressional direc-
tion,” a court cannot conclude that Congress “deprived the States of the
power to act.” Id., at 244. Because we conclude that the NLRA does
not arguably protect the Union's conduct, we need not address these
exceptions.
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drum located on the back of the truck, but only for a limited
ti
me. If concrete remains in the rotating drum for too long,
it will harden and cause signifcant damage to the truck.
Worse still, the hardening begins right away if the drum
stops revolving.
The International Brotherhood of Teamsters Local Union
No. 174 (Union) serves as the exclusive bargaining repre-
sentative for Glacier's truck drivers. After the collective-
bargaining agreement between Glacier and the Union ex-
pired in the summer of 2017, the parties negotiated in an
attempt to reach a new deal. Things did not go smoothly.
Tensions came to a head on the morning of August 11.
According to the allegations in Glacier's complaint, a Union
agent signaled for a work stoppage when the Union knew
that Glacier was in the midst of mixing substantial amounts
of concrete, loading batches into ready-mix trucks, and mak-
ing deliveries. Although Glacier quickly instructed drivers
to fnish deliveries in progress, the Union directed them to
ignore Glacier's orders. At least 16 drivers who had already
set out for deliveries returned with fully loaded trucks.
Seven parked their trucks, notifed a Glacier representative,
and either asked for instructions or took actions to protect
their trucks. But at least nine drivers abandoned their
trucks without a word to anyone.
Glacier faced an emergency. The company could not leave
the mixed concrete in the trucks because the concrete's inevi-
table hardening would cause signifcant damage to the vehi-
cles. At the same time, the company could not dump the
concrete out of the trucks at random because concrete con-
tains environmentally sensitive chemicals. To top it all off,
Glacier had limited time to solve this conundrum.
A mad scramble ensued. Glacier needed to determine
which trucks had concrete in them, how close the concrete
in each truck was to hardening, and where to dump that con-
crete in an environmentally safe manner. Over the course
of fve hours, nonstriking employees built special bunkers
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and managed to offoad the concrete. When all was said and
done
, Glacier's emergency maneuvers prevented damage to
its trucks. But the concrete that it had already mixed that
day hardened in the bunkers and became useless.
Glacier sued the Union for damages in Washington state
court. Relying on the allegations detailed above, Glacier
claimed that the Union intentionally destroyed the com-
pany's concrete and that this conduct amounted to common-
law conversion and trespass to chattels.
The Union moved to dismiss Glacier's tort claims on the
ground that the NLRA preempted them. In the Union's
view, the NLRA at least arguably protected the drivers'
conduct, so the State was powerless to hold the Union ac-
countable for any of the strike's consequences.
The trial court agreed with the Union. After the appel-
late court reversed, the Washington Supreme Court rein-
stated the trial court's decision. In its view, “the NLRA
preempts Glacier's tort claims related to the loss of its con-
crete product because that loss was incidental to a strike
arguably protected by federal law.” 198 Wash. 2d 768, 774,
500 P. 3d 119, 123 (2021).
We granted certiorari to resolve whether the NLRA pre-
empts Glacier's tort claims alleging that the Union intention-
ally destroyed its property during a labor dispute. 598
U. S. ––– (2022).
II
As the party asserting preemption, the Union bears the
burden of (1) advancing “an interpretation of the [NLRA]
that is not plainly contrary to its language and that has not
been `authoritatively rejected' by the courts or the Board,”
and then (2) putting forth “enough evidence to enable the
court to fnd that” the NLRA arguably protects the drivers'
conduct. Davis, 476 U. S., at 395. The Union passes the
frst test but fails the second.
All agree that the NLRA protects the right to strike but
that this right is not absolute. Brief for Petitioner 18; Brief

780 GLA
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for Respondent 21, 46, n. 14. The Board has long taken the
positi
on—which both the Union and Glacier accept—that the
NLRA does not shield strikers who fail to take “reasonable
precautions” to protect their employer's property from fore-
seeable, aggravated, and imminent danger due to the sudden
cessation of work. Bethany Medical Center, 328 N. L. R. B.
1094 (1999) (“concerted activity” is “indefensible where em-
ployees fail to take reasonable precautions to protect the em-
ployer's plant, equipment, or products from foreseeable im-
minent danger due to sudden cessation of work”); see also
Brief for Petitioner 14, 30–31; Brief for Respondent 28–29;
Reply Brief 6–7; Tr. of Oral Arg. 68, 86. Given this undis-
puted limitation on the right to strike, we proceed to con-
sider whether the Union has demonstrated that the statute
arguably protects the drivers' conduct. Davis, 476 U. S.,
at 395. We conclude that it has not.
2
The drivers engaged in a sudden cessation of work that
put Glacier's property in foreseeable and imminent danger.
The Union knew that concrete is highly perishable and that
it can last for only a limited time in a delivery truck's rotat-
ing drum. It also knew that concrete left to harden in a
truck's drum causes signifcant damage to the truck. The
Union nevertheless coordinated with truck drivers to initiate
the strike when Glacier was in the midst of batching large
quantities of concrete and delivering it to customers. Pre-
dictably, the company's concrete was destroyed as a result.
And though Glacier's swift action saved its trucks in the end,
the risk of harm to its equipment was both foreseeable and
2
The Union moved to dismiss Glacier's claims for failure to state a claim
and for lack of subject-matter jurisdiction. Like the Washington Supreme
Court, we treat both motions together and accept the allegations in the
complaint as true at the motion-to-dismiss stage. 198 Wash. 2d 768, 782–
783, 500 P. 3d 119, 127 (2021); see also Kinney v. Cook, 159 Wash. 2d 837,
842, 154 P. 3d 206, 209 (2007). Pursuant to Washington law, we also may
consider additional factual allegations made by Glacier that support its
complaint. See Bravo v. Dolsen Companies, 125 Wash. 2d 745, 750, 888
P. 2d 147, 150 (1995).
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serious. See NLRB v. Special Touch Home Care Services,
Inc.
, 708 F. 3d 447, 460 (CA2 2013) (“The appropriate inquiry
is focused on the risk of harm, not its realization”).
The Union failed to “take reasonable precautions to pro-
tect” against this foreseeable and imminent danger. Beth-
any Medical Center, 328 N. L. R. B., at 1094. It could have
initiated the strike before Glacier's trucks were full of wet
concrete—say, by instructing drivers to refuse to load their
trucks in the frst place. Once the strike was underway,
nine of the Union's drivers abandoned their fully loaded
trucks without telling anyone—which left the trucks on a
path to destruction unless Glacier saw them in time to unload
the concrete. Yet the Union did not take the simple step of
alerting Glacier that these trucks had been returned. Nor,
after the trucks were in the yard, did the Union direct its
drivers to follow Glacier's instructions to facilitate a safe
transfer of equipment. To be clear, the “reasonable precau-
tions” test does not mandate any one action in particular.
But the Union's failure to take even minimal precautions il-
lustrates its failure to fulfll its duty.
Indeed, far from taking reasonable precautions to mitigate
foreseeable danger to Glacier's property, the Union executed
the strike in a manner designed to compromise the safety of
Glacier's trucks and destroy its concrete. Such conduct is
not “arguably protected” by the NLRA; on the contrary, it
goes well beyond the NLRA's protections. See NLRB v.
Marshall Car Wheel & Foundry Co., 218 F. 2d 409, 411, 413
(CA5 1955) (strike unprotected when employees abandoned
their posts without warning “when molten iron in the plant
cupola was ready to be poured off,” even though “a lack of
suffcient help to carry out the critical pouring operation
might well have resulted in substantial property damage”).
Thus, accepting the complaint's allegations as true, the
Union did not take reasonable precautions to protect Gla-
cier's property from imminent danger resulting from the
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782 GLA
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Opinion of the Court
erred in dismissing Glacier's tort claims as preempted on
the
pleadings.
III
The Union resists this conclusion. First, it emphasizes
that the NLRA's protection of the right to strike should “ `be
given a generous interpretation.' ” Brief for Respondent 21
(quoting NLRB v. Erie Resistor Corp., 373 U. S. 221, 234–
235 (1963)). A strike, it points out, consists of a “concerted
stoppage of work.” § 142(2). So, the argument goes, by en-
gaging in a concerted stoppage of work to support their eco-
nomic demands, the drivers engaged in conduct arguably
protected by § 7 of the NLRA.
This argument oversimplifes the NLRA. As we ex-
plained, the right to strike is limited by the requirement that
workers “take reasonable precautions to protect the employ-
er's plant, equipment, or products from foreseeable imminent
danger due to sudden cessation of work.” Bethany Medical
Center, 328 N. L. R. B., at 1094. So the mere fact that
the drivers engaged in a concerted stoppage of work to sup-
port their economic demands does not end the analysis. We
must also ask whether the strike exceeded the limits of the
statute.
Second, the Union argues that “workers do not forfeit the
Act's protections simply by commencing a work stoppage at
a time when the loss of perishable products is foreseeable.”
Brief for Respondent 22. It points out that the Board has
found strikers' conduct protected even when their decision
not to work created a risk that perishable goods would
spoil. See, e. g., Lumbee Farms Coop., Inc., 285 N. L. R. B.
497 (1987) (raw poultry processing workers), enf 'd, 850 F. 2d
689 (CA4 1988); Central Okla. Milk Producers Assn., 125
N. L. R. B. 419 (1959) (milk-truck drivers), enf 'd, 285 F. 2d
495 (CA10 1960); Leprino Cheese Co., 170 N. L. R. B. 601
(1968) (cheese factory employees), enf 'd, 424 F. 2d 184 (CA10
1970). If the mere risk of spoilage is enough to render a
strike illegal, the Union insists, then workers who deal with
perishable goods will have no meaningful right to strike.
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Opinion of the Court
The Union is swinging at a straw man. It casts this case
as
one involving nothing more than a foreseeable risk that
the employer's perishable products would spoil. But given
the lifespan of wet concrete, Glacier could not batch it until
a truck was ready to take it. So by reporting for duty and
pretending as if they would deliver the concrete, the drivers
prompted the creation of the perishable product. Then,
they waited to walk off the job until the concrete was mixed
and poured in the trucks. In so doing, they not only de-
stroyed the concrete but also put Glacier's trucks in harm's
way. This case therefore involves much more than “a work
stoppage at a time when the loss of perishable products is
foreseeable.” Brief for Respondent 22.
Third, the Union maintains that the timing of the strike
and Glacier's lack of notice cannot render the drivers' con-
duct unprotected. Id., at 26–28. It argues that workers
are not required to time their strikes to minimize economic
harm to their employer, see Lumbee Farms, 285 N. L. R. B.,
at 506, and that the NLRA does not impose a legal require-
ment that workers give specifc notice of a strike's timing,
see Columbia Portland Cement Co. v. NLRB, 915 F. 2d 253,
257 (CA6 1990).
We agree that the Union's decision to initiate the strike
during the workday and failure to give Glacier specifc notice
do not themselves render its conduct unprotected. Still,
they are relevant considerations in evaluating whether strik-
ers took reasonable precautions, whether harm to property
was imminent, and whether that danger was foreseeable.
See International Protective Services, Inc., 339 N. L. R. B.
701, 702–703 (2003) (attempt “ `to capitalize on the element
of surprise' ” stemming from a lack of notice weighed in favor
of concluding that a union failed to take reasonable precau-
tions). In this instance, the Union's choice to call a strike
after its drivers had loaded a large amount of wet concrete
into Glacier's delivery trucks strongly suggests that it failed
to take reasonable precautions to avoid foreseeable, aggra-
vated, and imminent harm to Glacier's property.

784 GLA
CIER NORTHWEST, INC. v. TEAMSTERS
Opinion of the Court
Finally, the Union points out that the drivers returned the
tr
ucks to Glacier's facility. And it maintains that all of the
drivers left the drums of their trucks rotating, which delayed
the concrete's hardening process. In the Union's view, this
establishes that the drivers took reasonable precautions to
protect the trucks. Brief for Respondent 28–30.
We see it differently. That the drivers returned the
trucks to Glacier's facility does not do much for the Union—
refraining from stealing an employer's vehicles does not
demonstrate that one took reasonable precautions to protect
them. And Glacier's allegations do not support the Union's
assertion that all of the drivers left the drums rotating.
The Union relies on a vague remark by an unspecifed Union
agent to another unspecifed person to leave a truck running.
See id., at 9, 30; Brief for Petitioner 8; App. 34. This snippet
does not show that all of the drivers left their trucks run-
ning, and even if it did, that would not necessarily mean
that the delivery trucks' drums continued rotating. In any
event, Glacier alleged that if concrete remains in a ready-
mix truck for too long, it will harden and cause signifcant
damage to the truck. The rotating drum forestalls that
hardening for a time, but not indefnitely. And the Union
concedes that the NLRA does not arguably protect its ac-
tions if they posed a material risk of harm to the trucks.
Tr. of Oral Arg. 78.
3
***
Glacier alleges that the drivers' conduct created an emer-
gency in which it had to devise a way to offoad concrete “in a
3
After the Washington Supreme Court affrmed the dismissal of Gla-
cier's tort claims, the Board's general counsel issued a complaint alleging
that Glacier engaged in unfair labor practices in relation to its labor dis-
pute with the drivers, including by disciplining some of those involved in
the strike. The lower courts have not addressed the signifcance, if any,
of the Board's complaint with respect to Garmon preemption. We will
not do so in the frst instance. Cutter v. Wilkinson, 544 U. S. 709, 718,
n. 7 (2005) (“[W]e are a court of review, not of frst view”). The Board's
general counsel agrees that this issue is not properly before us. See Brief
for United States as Amicus Curiae 28.
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785
Thomas, J., concurring in judgment
timely manner to avoid costly damage to [its] mixer trucks.”
App
. 72. The Union's actions not only resulted in the de-
struction of all the concrete Glacier had prepared that day;
they also posed a risk of foreseeable, aggravated, and immi-
nent harm to Glacier's trucks. Because the Union took af-
frmative steps to endanger Glacier's property rather than
reasonable precautions to mitigate that risk, the NLRA does
not arguably protect its conduct. We reverse the judgment
of the Washington Supreme Court and remand the case for
further proceedings not inconsistent with this opinion.
It is so ordered.
Justice Thomas, with whom Justice Gorsuch joins,
concurring in the judgment.
I agree that petitioner's state-court claims are not pre-
empted by the National Labor Relations Act (NLRA). The
majority reaches this conclusion, however, by applying the
Court's precedent in San Diego Building Trades Council v.
Garmon, 359 U. S. 236 (1959), which held that state courts
are disabled from adjudicating state-law claims that concern
conduct “arguably” protected under the NLRA. Id., at
245–246. Because this Court has previously held that the
type of conduct alleged here is not protected, I join Jus-
tice Alito's opinion concurring in the judgment. I write
separately to emphasize the oddity of Garmon's broad pre-
emption regime.
This Court typically applies a high bar before concluding
that federal law “strip[s] state courts of jurisdiction to hear
their own state claims.” Atlantic Richfeld Co. v. Christian,
590 U. S. –––, ––– – –––. Likewise, the Court generally re-
quires a “clear” purpose to displace state law before fnding
that a federal statute does so. Wyeth v. Levine, 555 U. S.
555, 565 (2009) (internal quotation marks omitted).
As the majority notes, however, Garmon “goes beyond the
usual preemption rule.” Ante, at 776. In Garmon, the
Court determined that, “[w]hen an activity is arguably sub-
ject to § 7 or § 8 of the Act” (which, respectively, concern
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CIER NORTHWEST, INC. v. TEAMSTERS
Thomas, J., concurring in judgment
employees' right to engage in concerted activity and unfair
labor
practices), “the States as well as the federal courts
must defer to the exclusive competence of the National
Labor Relations Board [(NLRB or Board)].” 359 U. S., at
245. The Court went on to explain that this prophylactic
rule of pre-emption may apply even to state-court claims
arising under state private law (rather than the NLRA or a
comparable state regulatory scheme) and even to claims
seeking remedies not available from the Board. Id., at 246–
248.* Nor, under the Court's rule, is the State's power to
act restored if the NLRB “fail[s] to determine the status of
the disputed conduct by declining to assert jurisdiction, or
by refusal . . . to fle a charge; or by adopting some other
disposition which does not defne the nature of the activity
with unclouded legal signifcance.” Id., at 245–246.
Garmon acknowledged that the NLRA's pre-emption im-
plications “ `are of a Delphic nature,' ” leaving the States' re-
sidual power in a “ `penumbral area [that] can be rendered
progressively clear only by the course of litigation.' ” Id., at
240–241 (quoting Machinists v. Gonzales, 356 U. S. 617, 619
(1958); Weber v. Anheuser-Busch, Inc., 348 U. S. 468, 480–481
(1955)). It thus emphasized that “Congress has entrusted
administration of the labor policy for the Nation to a central-
ized administrative agency,” making it “essential to the ad-
ministration of the Act” that determinations about protected
and prohibited conduct “be left in the frst instance to the
[NLRB].” 359 U. S., at 242, 244–245. To do otherwise, it
feared, “would create potential frustration of national pur-
*Nonetheless, and motivated by “due regard for the presuppositions of
our embracing federal system,” Garmon carved out two areas of presump-
tive state control: (1) “where the activity regulated was a merely periph-
eral concern of the [NLRA as amended],” and (2) where it “touched inter-
ests so deeply rooted in local feeling and responsibility that, in the absence
of compelling congressional direction, [the Court] could not infer that Con-
gress had deprived the States of the power to act.” 359 U. S., at 243–244.
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Thomas, J., concurring in judgment
poses” and invite “the danger of state interference with na-
ti
onal policy.” Id., at 244–245.
Justice Harlan concurred in the result, warning that the
majority's rule would “reduc[e] to the vanishing point”
States' “power to redress wrongful acts in the labor feld”
and provide any “effective remedy under their own laws for
. . . tortious conduct.” Id., at 253–254. The years since
have borne out that warning. Garmon elevates “even the
remotest possibility of confict,” thereby “overstat[ing] the
likelihood and signifcance of conficts and . . . set[ting] up
an unreal goal of doctrinal and factual harmony.” L. Jaffe,
Primary Jurisdiction, 77 Harv. L. Rev. 1037, 1053 (1964). In
effect, “Garmon doctrine completely pre-empts state-court
jurisdiction unless the Board determines that the disputed
conduct is neither protected nor prohibited by the [NLRA].”
Sears, Roebuck & Co. v. Carpenters, 436 U. S. 180, 199,
n. 29 (1978).
The majority opinion today underscores the strangeness
of the Garmon regime. Here, the Supreme Court of the
United States reassures a state court of its power to adjudi-
cate a state-law tort claim. The Court does so, not based on
its own judgment that federal law does not pre-empt the
claim, but because the NLRB's existing precedents ade-
quately remove any “[c]lou[d]” over the matter. 359 U. S.,
at 246. But, if the Board's precedents left the matter “argu-
able” (and the NLRA did not plainly dictate an answer), then
the state courts would be “ousted” of jurisdiction. Long-
shoremen v. Davis, 476 U. S. 380, 396 (1986). The upshot of
this approach appears to be that the scope of the NLRA's
pre-emption of state-court jurisdiction over state claims is
defned—not by the statutory text—but by “penumbra[s]”
that wax and wane as the Board develops, or declines to de-
velop, its own carefully insulated common law of labor rela-
tions. Garmon, 359 U. S., at 240 (internal quotation marks
omitted).
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CIER NORTHWEST, INC. v. TEAMSTERS
Alito, J., concurring in judgment
The parties here have not asked us to reconsider Garmon,
nor
is it necessary to do so to resolve this case. Nonethe-
less, in an appropriate case, we should carefully reexamine
whether the law supports Garmon's “unusual” pre-emption
regime. Ante, at 776. In doing so, I would bear in mind
that any proper pre-emption inquiry must focus on the
NLRA's text and ask whether federal law and state law “are
in logical contradiction,” such that it is impossible to comply
with both. Merck Sharp & Dohme Corp. v. Albrecht, 587
U. S. –––, ––– (2019) (Thomas, J., concurring); see also
PLIVA, Inc. v. Mensing, 564 U. S. 604, 617–618 (2011).
Justice Alito, with whom Justice Thomas and Justice
Gorsuch join, concurring in the judgment.
I agree with the Court that the Washington Supreme
Court erred in holding that Glacier Northwest's complaint
is preempted under San Diego Building Trades Council v.
Garmon, 359 U. S. 236 (1959). The National Labor Rela-
tions Act (NLRA) protects the right to strike, but that right
is subject to certain limitations and qualifcations, see 29
U. S. C. § 163, and this Court's decisions make clear that the
Act does not protect striking employees who engage in the
type of conduct alleged here.
This Court has long recognized that the Act does not “in-
vest those who go on strike with an immunity from discharge
for acts of trespass or violence against the employer's prop-
erty.” NLRB v. Fansteel Metallurgical Corp., 306 U. S. 240,
255 (1939). To justify “despoiling [an employer's] property”
or “the seizure and conversion of its goods,” we have rea-
soned, “would be to put a premium on resort to force instead
of legal remedies.” Id., at 253. It follows that Garmon
preemption does not prevent States from imposing liability
on employees who intentionally destroy their employer's
property. See, e. g., Machinists v. Wisconsin Employment
Relations Comm'n, 427 U. S. 132, 136 (1976) (“Policing . . .
destruction of property has been held most clearly a matter
for the States”); Construction Workers v. Laburnum Constr.

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789
Jackson, J., dissenting
Corp., 347 U. S. 656, 669 (1954) (The NLRA does not allow
employees
to “destroy property without liability for the dam-
age done”); Electrical Workers v. Wisconsin Employment
Relations Bd., 315 U. S. 740, 748 (1942) (The NLRA “was
not designed to preclude a State” from regulating threats of
property damage); see also Linn v. Plant Guard Workers,
383 U. S. 53, 61–62 (1966) (“ `[T]here is no ground for conclud-
ing that existing criminal penalties or liabilities for tortious
conduct have been eliminated' ” by the NLRA); Bill John-
son's Restaurants, Inc. v. NLRB, 461 U. S. 731, 741–742
(1983) (“It has . . . repeatedly been held that an employer has
the right to seek local judicial protection from tortious con-
duct during a labor dispute”).
Nothing more is needed to resolve this case. Glacier's
complaint alleges that the Union and its members acted
“with the improper purpose to harm Glacier by causing [its]
batched concrete to be destroyed.” App. 10; accord, id.,
at 14, 19–20. As the Court recognizes, they succeeded by
“prompt[ing] the creation of the perishable product” and
then ceasing work when the concrete was in a vulnerable
state. Ante, at 783 (emphasis deleted); see App. 10–13. Be-
cause this Court has long rejected the Union's claim that this
kind of conduct is protected, Garmon preemption does not
apply. See Longshoremen v. Davis, 476 U. S. 380, 395
(1986).*
Justice Jackson, dissenting.
The right to strike is fundamental to American labor law.
Congress enshrined that right in the National Labor Rela-
tions Act (NLRA) and simultaneously established the Na-
*The Court wisely declines to address the argument on which Justice
Jackson relies regarding the effect of the complaint before the NLRB on
this litigation. See post, at 796–799 (dissenting opinion). That argument
represents a striking extension of Garmon preemption, which, as the
Court notes, is already an “unusual” doctrine. See ante, at 776. If the
state courts on remand dismiss this case on that ground, the decision, in
my judgment, would be a good candidate for a quick return trip here.
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CIER NORTHWEST, INC. v. TEAMSTERS
Jackson, J., dissenting
tional Labor Relations Board to adjudicate disputes that
ar
ise between workers and management. That decision re-
fected Congress's judgment that an agency with specialized
expertise should develop and enforce national labor law in a
uniform manner, through case-by-case adjudication. For its
part, this Court has scrupulously guarded the Board's au-
thority for more than half a century. See San Diego Build-
ing Trades Council v. Garmon, 359 U. S. 236 (1959). Under
Garmon, and as relevant here, a court presented with a tort
suit based on strike conduct generally must pause proceed-
ings and permit the Board to determine in the frst instance
whether the union's conduct is lawful if the conduct at issue
is even “arguably” protected by the NLRA. Id., at 245.
Today, the Court falters. As the majority acknowledges,
the Board's General Counsel has fled a complaint with the
Board after a thorough factual investigation, and that com-
plaint alleges that the NLRA protects the strike conduct at
the center of this state-court tort suit. The logical implica-
tion of a General Counsel complaint under Garmon is that
the union's conduct is at least arguably protected by the
NLRA. Consequently, where (as here) there is a General
Counsel complaint pending before the Board, courts—includ-
ing this Court—should suspend their examination. Garmon
makes clear that we have no business delving into this par-
ticular labor dispute at this time.
But instead of modestly standing down, the majority ea-
gerly inserts itself into this confict, proceeding to opine on
the propriety of the union's strike activity based on the facts
alleged in the employer's state-court complaint. As part of
this mistaken expedition, the majority tries its own hand at
applying the Board's decisions to a relatively novel scenario
that poses diffcult line-drawing questions—fact-sensitive is-
sues that Congress plainly intended for the Board to address
after an investigation. And in the course of inappropriately
weighing in on the merits of those questions at this stage,
the majority also misapplies the Board's cases in a manner
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791
Jackson, J., dissenting
that threatens to both impede the Board's uniform develop-
ment
of labor law and erode the right to strike.
In my view, today's misguided foray underscores the wis-
dom of Congress's decision to create an agency that is
uniquely positioned to evaluate the facts and apply the law
in cases such as this one. This case is Exhibit A as to why
the Board—and not the courts—should ordinarily take the
frst crack at resolving contentious, fact-bound labor disputes
of this nature. Because the majority's ruling suggests oth-
erwise, I respectfully dissent.
I
The majority's brief opinion quotes Garmon's “arguably
protected” test and endeavors to apply it. Ante, at 776–777,
779–784. But the opinion devotes relatively little space to
the origins and purpose of that longstanding precedent.
That omission is telling. A proper understanding of Gar-
mon's foundation sheds considerable light on the majority's se-
quential missteps in this case.
A
Congress's passage of the NLRA “marked a fundamental
change in the Nation's labor policies.” Sears, Roebuck & Co.
v. Carpenters, 436 U. S. 180, 190 (1978). Prior to that point,
union activity had been viewed as “a species of `conspiracy,' ”
prompting substantial confict between labor and manage-
ment. Ibid. With the enactment of the NLRA in 1935,
“Congress expressly recognized that collective organization
of segments of the labor force into bargaining units capable
of exercising economic power comparable to that possessed
by employers may produce benefts for the entire economy
in the form of higher wages, job security, and improved
working conditions.” Ibid.
The heart of the NLRA is § 7, which safeguards workers'
rights “to self-organization, to form, join, or assist labor or-
ganizations, to bargain collectively through representatives
of their own choosing, and to engage in other concerted activ-
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Jackson, J., dissenting
ities for the purpose of collective bargaining or other mutual
aid
or protection.” 29 U. S. C. § 157. Among the “ `con-
certed activities' ” that the Act unquestionably protects is
“the vital, economic instrumen[t] of the strike.” Garmon,
359 U. S., at 241; see § 163.
Section 8 of the NLRA provides a list of “unfair labor prac-
tice[s]” that employers and unions are prohibited from en-
gaging in. § 158. For example, it is an unfair labor practice
for an employer to “interfere with, restrain, or coerce em-
ployees in the exercise of ” their § 7 rights, including the right
to strike. § 158(a)(1). And it is an unfair labor practice for
a union to “refuse to bargain collectively with an employer.”
§ 158(b)(3). Taken together, § 7 and § 8 establish certain con-
duct that Congress has deemed protected (§ 7) and prohib-
ited (§ 8).
B
Congress could have stopped there. But “Congress did
not merely lay down a substantive rule of law to be enforced
by any tribunal competent to apply law generally to the
parties.” Garner v. Teamsters, 346 U. S. 485, 490 (1953).
Rather, Congress “went on to confde primary interpretation
and application of its rules to a specifc and specially consti-
tuted tribunal”: the National Labor Relations Board. Ibid.;
see generally §§ 153–156.
By statutory mandate, the Board is composed of fve mem-
bers who are appointed by the President with the advice and
consent of the Senate. § 153(a). Congress also provided for
an independent General Counsel, who is likewise presiden-
tially appointed and Senate confrmed. § 153(d); see NLRB
v. Food & Commercial Workers, 484 U. S. 112, 117–118
(1987). The General Counsel conducts investigations into
unfair labor practices and brings complaints before the
Board through a “particular procedure” that Congress has
prescribed “for investigation, complaint and notice, and hear-
ing and decision, including judicial relief pending a fnal ad-
ministrative order” from the Board. Garner, 346 U. S., at
490; see §§ 153, 160.
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793
Jackson, J., dissenting
The Board has feshed out this process via rulemaking au-
thor
ity that Congress has delegated. § 156. If a person be-
lieves that an employer or union has committed an unfair
labor practice, the person may fle a charge with a regional
director, who acts on behalf of the General Counsel. 29
CFR § 101.2 (2022). The regional director investigates the
charge. § 101.4. If “the charge appears to have merit and
efforts to dispose of it by informal adjustment are unsuccess-
ful,” the regional director issues a complaint on behalf of the
General Counsel. § 101.8. When a General Counsel's com-
plaint issues, an administrative law judge (ALJ) holds a hear-
ing and issues a decision, which the Board reviews if any
party fles an exception. §§ 101.8–101.12. If the Board
fnds that a party has engaged in an unfair labor practice, it
must order the party to “cease and desist” and to take “such
affrmative action . . . as will effectuate the policies” of the
NLRA. 29 U. S. C. § 160(c).
C
The history and structure of the NLRA make clear that
Congress “entrusted administration of the labor policy for
the Nation to a centralized administrative agency”—the
Board—“armed with its own procedures, and equipped with
its specialized knowledge and cumulative experience.” Gar-
mon, 359 U. S., at 242. Congress thought the Board's pri-
mary role was “necessary to obtain uniform application of
[the NLRA's] substantive rules and to avoid th[e] diversities
and conficts likely to result from a variety of local proce-
dures and attitudes toward labor controversies.” Garner,
346 U. S., at 490. That judgment makes perfect sense. The
NLRA's substantive principles are intrinsically broad and
potentially conficting, leaving much for future articulation
through case-by-case adjudication. Drawing the line be-
tween activities that constitute a protected strike, on the one
hand, and unprotected actions for which employers may val-
idly discipline employees, on the other, is a legally and fac-
tually complex task. Moreover, that task implicates im-
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CIER NORTHWEST, INC. v. TEAMSTERS
Jackson, J., dissenting
portant economic policy considerations about the relative
bargai
ning power of labor and management that affect not
only the parties to a particular labor dispute but also our
broader national economy.
To effect Congress's intent, this Court has consistently
recognized that “courts are not primary tribunals to adjudi-
cate [these] issues.” Garmon, 359 U. S., at 244. Rather, “it
is to the Board that Congress entrusted the task of applying
the Act's general . . . language in the light of the infnite
combinations of events which might be charged as violative
of its terms.” Beth Israel Hospital v. NLRB, 437 U. S. 483,
500–501 (1978) (internal quotation marks omitted). And the
Board, “if it is to accomplish the task which Congress set for
it, necessarily must have authority . . . to fll the interstices
of the broad statutory provisions.” Id., at 501. So, while
the Board's decision “is not the last word” on these complex
matters—given that its decisions are subject to review in
federal court—“it must assuredly be the frst.” Marine
Engineers v. Interlake S. S. Co., 370 U. S. 173, 185 (1962)
(emphasis added).
For that reason, this Court has long held that courts pre-
sented with claims arising out of a labor dispute must some-
times pause their proceedings to permit the Board to con-
sider the dispute in the frst instance. As relevant here, we
have held that if § 7—including its protection of the right to
strike—“arguably” protects the conduct at issue in a state-
court suit, then the court must await the Board's word as to
whether the conduct is, in fact, protected. Garmon, 359
U. S., at 245.
To determine whether conduct is “arguably protected,” a
state court examines the showing of the party invoking Gar-
mon and seeking to pause the litigation. The court asks
whether that party has (1) “advance[d] an interpretation of
the [NLRA] that is not plainly contrary to its language and
that has not been `authoritatively rejected' by the courts or
the Board,” and (2) “put forth enough evidence to enable the
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795
Jackson, J., dissenting
court to fnd that the Board reasonably could uphold a claim
based
on such an interpretation.” Longshoremen v. Davis,
476 U. S. 380, 395 (1986). If so, the state court must pause
proceedings to allow the Board to consider the complex legal
and factual contours of the question whether the union's con-
duct is actually protected by the NLRA.
The majority refers to this as “Garmon preemption,” in
keeping with historical practice. Ante, at 776. But the
term “preemption” is something of a misnomer. Rather
than entirely and automatically precluding the state-court
suit, the rule instead requires state courts to take a “juris-
dictional hiatus” while the Board considers the dispute in the
frst instance. Sears, Roebuck & Co., 436 U. S., at 203. If
the Board determines (subject to judicial review) that § 7
protects the union's conduct, normal confict preemption
kicks in: A state court may not hold a union liable on state-
law claims for conduct that is protected by the NLRA. See
Brown v. Hotel Employees, 468 U. S. 491, 503 (1984). But
“if the Board decides that the conduct is not protected,”
the state court may proceed to “entertain the litigation.”
Davis, 476 U. S., at 397.
1
With these general principles in mind, I now turn to the
particulars of this case.
II
This suit arises out of a union-organized strike. Peti-
tioner Glacier Northwest is a concrete-delivery company, and
1
Justice Thomas seeks to undercut our Garmon precedent by describ-
ing it as “od[d]” and “strang[e]” relative to “ `the usual preemption rule.' ”
Ante, at 785, 787 (opinion concurring in judgment). But, as discussed, the
Garmon rule is not a standard preemption doctrine; it is different because
it is doing different work. Garmon protects Congress's judgment that
the Board, not state or federal courts, should be generally responsible
for the development of our Nation's labor law. The required pause when
Garmon's “arguably protected” test is satisfed allows for effcient resolu-
tion of the dispute prior to the expenditure of state judicial resources, and
the temporary nature of the pause makes it narrower, not broader, in
effect than ordinary preemption.

796 GLA
CIER NORTHWEST, INC. v. TEAMSTERS
Jackson, J., dissenting
respondent International Brotherhood of Teamsters Local
U
nion No. 174 (Union) represents Glacier's concrete-delivery
truckdrivers. After the drivers went on strike, Glacier sent
disciplinary letters to some of the drivers. The Union fled
an unfair labor practice charge with the Board, alleging that
the disciplinary letters were unlawful retaliation against the
drivers for engaging in strike conduct that is protected by
the NLRA.
Glacier then fled a complaint in Washington state court,
alleging that the Union engaged in tortious conduct when it
instructed the drivers to strike at a time when there was
wet concrete in some of the company's delivery trucks. In
response, the Union fled another Board charge, maintain-
ing that Glacier's lawsuit constituted additional unlawful
retaliation.
With respect to Glacier's tort suit, the Washington courts
engaged in the standard Garmon inquiry, ultimately result-
ing in a determination by the Washington Supreme Court
that the lawsuit could not proceed because the Union's strike
conduct was arguably protected by the NLRA. Glacier
sought, and we granted, certiorari to review that decision.
Notably, however, after the Washington Supreme Court is-
sued its decision, the regional director acting on behalf of
the Board's General Counsel fled an administrative com-
plaint against Glacier. In my view, for the reasons ex-
plained below, that subsequent event has greatly simplifed
the Garmon question.
A
The fling of the General Counsel's administrative com-
plaint necessarily suffces to establish that the Union's strike
conduct is “arguably protected” within the meaning of Gar-
mon. Thus, the General Counsel's complaint should have
marked the end of any court involvement in this matter at
this time.
The General Counsel's complaint alleges that Glacier inter-
fered with strike conduct protected by § 7 when it disciplined
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Jackson, J., dissenting
its drivers for walking off the job and when it fled this tort
suit.
That complaint represents the General Counsel's con-
clusion—reached after an extensive independent investiga-
tion involving collecting testimony and other evidence, and
after careful consideration of the competing legal principles
and policy concerns—that the Union's claim that its strike
conduct was protected “appears to have merit.” 29 CFR
§§ 101.4, 101.8. One “cannot credibly contend that a claim
that makes it through this gauntlet does not concern conduct
`arguably' protected by the NLRA.” Davis Supermarkets,
Inc. v. NLRB, 2 F. 3d 1162, 1179 (CADC 1993); accord,
Makro, Inc., 305 N. L. R. B. 663, 670 (1991).
A court presented with a General Counsel complaint
should therefore fnd Garmon inherently satisfed. This is
so because the entire point of Garmon's arguably-protected
test is to permit the court to assess the facts and relevant
labor law in service of a gatekeeping function. The answer
to the Garmon question simply (and solely) establishes
whether the court can continue to entertain a lawsuit that
relates to the challenged strike conduct, or whether the legal
action must be suspended to allow the Board to make an
initial assessment of the matter. The court evaluates the
existing evidence and the law for a specifc reason: to deter-
mine whether the lawsuit attacks arguably-protected con-
duct such that entertaining the legal action will interfere
with the Board's prerogative to develop the facts and adjudi-
cate the merits of the dispute as part of the Board's broader
authority to develop national labor law.
If the General Counsel investigates the matter and fles a
complaint with the Board alleging that the union's conduct
is protected, it becomes indisputable that the pending legal
action might interfere with the Board's authority. Thus, a
General Counsel complaint relieves the court of the burden
of having to make the arguably-protected assessment based
on its own understanding of the evidence and labor law—it
is “arguable” that the union's conduct is protected because
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the General Counsel is arguing just that. To be sure, we
have
said that the arguably-protected test is “not without
substance” and is “not satisfed by a conclusory assertion of
pre-emption.” Davis, 476 U. S., at 394. But an allegation
from the Board's General Counsel after a thorough investiga-
tion is a far cry from a “conclusory assertion” of protection.
2
What is more, by virtue of the General Counsel's com-
plaint, the Board is, at this very moment, exercising its au-
thority to adjudicate the merits of this dispute. On Janu-
ary 11, 2023, an ALJ denied Glacier's motion to postpone the
ALJ hearing on the General Counsel's complaint pending
this Court's decision in this case. As the ALJ explained, the
General Counsel's pleading “constituted a determination that
the strikers' conduct was at least arguably protected by the
[NLRA] and that this agency became the exclusive forum for
adjudicating whether the strikers' conduct was protected.”
3
A nine-day hearing ensued, and the parties completed post-
hearing briefng last week. We have said that “[t]he need
for protecting the exclusivity of [the Board's] jurisdiction is
obviously greatest when the precise issue brought before a
court is in the process of litigation through procedures origi-
nating in the Board.” Marine Engineers, 370 U. S., at 185.
That is exactly the situation here.
For these reasons, I believe that the fling of the General
Counsel's complaint is more than suffcient to trigger Gar-
mon's pause, and that it must be so if consistency with
Congress's intent to give the Board primary authority to in-
terpret and enforce the NLRA is to be maintained. In cir-
cumstances like these, “the States as well as the federal
courts must defer to the exclusive competence of the Na-
2
This is not to suggest that the General Counsel's complaint is the end
of the story, as the Board may ultimately disagree with the factual or legal
basis of that pleading. But the complaint is surely suffcient to establish
arguable protection, such that a court should stay its hand.
3
Order Denying Motion for Postponement of Hearing in Glacier North-
west, Inc., Nos. 19–CA–203068, 19–CA–211776, p. 7.
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Jackson, J., dissenting
tional Labor Relations Board.” Garmon, 359 U. S., at 245.
And
this Court is no exception. Because the General Coun-
sel has now fled a complaint with the Board concerning the
labor dispute at issue in this case, all courts—including this
one—should stand down.
B
The majority does not take issue with my conclusion that
the General Counsel's complaint triggers a Garmon hiatus;
instead, it takes no position on the matter, leaving the ques-
tion open for the Washington courts to decide on remand.
Ante, at 784, n. 3.
The majority's reason for declining to address this argu-
ment is noteworthy. It explains that, because the General
Counsel's complaint was fled after the Washington Supreme
Court had affrmed the dismissal of Glacier's complaint on
Garmon grounds, “[t]he lower courts have not addressed the
signifcance, if any, of the Board's complaint with respect to
Garmon preemption.” Ante, at 784, n. 3. And since we are
“ `a court of review, not of frst view,' ” ibid. (quoting Cutter
v. Wilkinson, 544 U. S. 709, 718, n. 7 (2005)), the majority
declines to “do so in the frst instance.” Ante, at 784, n. 3.
This rationale is inconsistent with the broader approach
that the majority takes in this case. It would be one thing
if the Court simply noted the fling of the General Counsel's
complaint and authorized the lower courts to evaluate the
impact of that complaint on the Garmon question in the frst
instance. But it goes further: The majority also inserts it-
self into the midst of this labor dispute now (despite the Gen-
eral Counsel's complaint), proceeding to apply the Board's
cases to novel and diffcult line-drawing questions and ulti-
mately concluding that the strike conduct alleged in Glacier's
complaint is not even arguably protected.
The majority cannot have it both ways. A concern about
the Court's institutional role justifes, at most, vacating the
judgment below and remanding for the lower court to con-
sider the import of the General Counsel's complaint. The
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same observation that compels the majority to allow for such
lower-cour
t consideration—that we are “ `a court of review,
not of frst view,' ” ante, at 784, n. 3—should have likewise
led it to decline to intrude into this labor dispute while it is
pending before the Board.
III
For the reasons discussed above, I would have vacated the
Washington Supreme Court's judgment and remanded with
directions to stay proceedings or dismiss Glacier's complaint
without prejudice, on the straightforward ground that the
General Counsel's complaint triggers the jurisdictional hia-
tus that Garmon requires.
4
The majority sidesteps my preferred resolution of this
matter and instead proceeds to engage in Garmon's “argu-
ably protected” test by applying a series of fact-intensive
Board decisions to the bare allegations in Glacier's state-
court complaint. To do this, the majority invokes the
Board's “reasonable precautions” principle. Ante, at 779–
782. That principle (discussed in Part IV, infra) is derived
from the Board's determination that striking workers must
take reasonable precautions to protect persons, the employ-
er's premises, and its equipment from foreseeable, aggra-
vated, and imminent harm due to the sudden cessation of
work. The majority has taken it upon itself to apply the
Board's reasonable-precautions principle to the factual alle-
gations about the Union's conduct that Glacier alleges in this
lawsuit, and it thereby concludes that the drivers' conduct is
not even arguably protected by the NLRA.
This course of action (which is already confounding given
that the Board itself is currently considering the challenged
strike conduct with the beneft of developed facts and labor
4
The Washington Supreme Court affrmed the dismissal of Glacier's
claims. Because only a pause of the state-court litigation is necessary
under Garmon, the proper disposition is either a stay of proceedings or
dismissal without prejudice.
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Jackson, J., dissenting
law expertise) refects an analytical approach to the issues
presented
that cannot be squared with Garmon.
A
Whether the NLRA protects particular strike conduct
often turns on subtle factual disputes and nuanced legal dis-
tinctions. Here, for example, whether the Union's strike
conduct is protected or unprotected might well depend on
whether the drivers left the concrete-delivery trucks' revolv-
ing drums turning when they walked off the job. So, too,
might it depend on fne legal gradations concerning how im-
minent or how aggravated the risk of harm must be to trig-
ger the duty to take reasonable precautions. These kinds
of determinations cry out for evidentiary hearings, and in
this highly fact-sensitive area of the law, which generally
develops on a case-by-case basis, the scope of NLRA protec-
tion in a given set of circumstances is typically determined
once the facts have been established—through discovery, de-
bate, and sometimes the tedious work of making contentious
credibility determinations.
Fortunately, in this regard, Congress has gifted our legal
system with an expert agency that thoroughly investigates
what happened—i. e., the facts of strike-related labor dis-
putes—and then engages in the initial task of answering the
sometimes complex, always fact-bound question whether the
NLRA protects the strike conduct at issue. Meanwhile, a
court that is undertaking Garmon's arguably-protected anal-
ysis is engaged in a fundamentally different inquiry. As ex-
plained in Part II–A, supra, while the court is most certainly
considering strike conduct arising from a labor dispute, it is
not meant to address the merits of these complex questions.
Under the NLRA and Garmon, courts must take as a given
that the Board is the entity to which Congress has assigned
responsibility for initially determining what happened and
taking the frst crack at deciding whether the NLRA pro-
tects the uni on's conduct. And far from usurping that
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Board function, Garmon tasks the court with merely con-
duc
ting a threshold, gatekeeping assessment of whether the
lawsuit before it must be paused, or whether the suit can
proceed because it is not even arguable that the conduct at
issue in the lawsuit is protected by the NLRA.
To avoid veering into the Board's assigned territory, it is
crucial that the courts have a clear understanding of the na-
ture of the Garmon assessment and what it requires. The
court asks, frst of all, whether the party invoking Garmon
has “advance[d] an interpretation of the [NLRA] that is not
plainly contrary to its language and that has not been `au-
thoritatively rejected' by the courts or the Board.” Davis,
476 U. S., at 395. This inquiry involves merely comparing
the union's claim about the scope of its protection to the
broad protec tive lang uage of the st atute and decidi ng
whether the union's interpretation has already been defni-
tively rejected either by courts or by the Board.
The second task is to determine whether the party invok-
ing Garmon has “put forth enough evidence to enable the
court to fnd that the Board reasonably could uphold a claim
based on such an interpretation.” Davis, 476 U. S., at 395.
Again, this is not an invitation to supplant the Board's fact-
fnding role or to usurp the authority that Congress has
given the Board to make the initial underlying protected-or-
unprotected determination. Rather, the point of this part
of the Garmon assessment is simply to determine whether
it is arguable that the Board—in the exercise of its discre-
tion to develop labor law and aided by its investigation into
the facts—could conclude that the strike conduct at issue is
protected by the NLRA. See 359 U. S., at 245.
Thus, consistent with a statutory scheme that gives pri-
macy to the agency's expertise, a court's task under Garmon
is unmistakably modest. It must merely assess whether, in
light of existing law and the evidence that has been amassed
related to this strike, it is possible that the union could pre-
vail before the Board. Put another way, instead of stepping

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803
Jackson, J., dissenting
into the Board's shoes as primary factfnder, or even prog-
nosticati
ng about what the Board is likely to decide concern-
ing the extent of NLRA coverage, a court that stands down
upon a proper Garmon analysis has simply determined (1)
that existing law does not plainly and authoritatively pro-
hibit the strike conduct at issue, and (2) that evidence exists
concerning how the strike was conducted that might ulti-
mately favor the union, such that the lawsuit should pause
to allow the Board to gather the facts and apply its expertise
to determine whether the strike was lawful.
B
The majority seems to misunderstand all this in the con-
text of this case. It correctly concludes that the Union has
carried its burden of “advancing an interpretation of the
[NLRA] that is not plainly contrary to its language and that
has not been authoritatively rejected by the courts or the
Board.” Ante, at 779 (internal quotation marks omitted).
But it fnds that the Union has failed to satisfy the second
Garmon step, and it does so after undertaking its own as-
sessment of the facts alleged in Glacier's complaint and
endeavoring to apply the Board's fact-bound reasonable-
precautions precedents. See, e. g., ante, at 780–781 (deter-
mining, based on alleged facts, that “[t]he drivers engaged in
a sudden cessation of work that put Glacier's property in
foreseeable and imminent danger” and that the risk of harm
to the concrete-delivery trucks was “both foreseeable and
serious”); ante, at 781 (concluding that “[t]he Union failed to
`take reasonable precautions,' ” after hypothesizing various
steps that, according to the majority, the Union should have
taken but did not).
Given what I have already said about Garmon's purpose
and what it calls for, the majority's error in proceeding in
this fashion is obvious. To my mind, if a court that is evalu-
ating what to do per Garmon fnds itself weighing in on such
fact-bound matters as whether the strike posed a risk of
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harm that was aggravated enough or imminent enough to
remove
NLRA protection, or starts contemplating whether
the precautions that the striking employees took to address
any such risk were reasonable enough to allow them to retain
the right to strike, it has unwittingly wandered into a do-
main that Congress intentionally assigned to the Board to
address in the frst instance.
5
It is clear to me that Congress plainly intended for the
Board's factfnding function to be at the forefront of this kind
of legal evaluation. Thus, in my view, when a court under-
takes the Garmon analysis in a context such as this one, it
should take care to limit itself to its own assigned responsi-
bility: the mere determination of whether, given the union's
evidence and legal interpretation, the Board could possibly
conclude that the union had taken reasonable precautions.
If yes, the court should suspend the pending legal action to
let the Board decide the question. To conclude no, given the
fact-bound nature of the reasonable-precautions analysis, a
court in all but the most exceptional circumstances will need
to be able to point to a reasonable-precautions case from the
Board that is on all fours with the facts of the case before it
and that found the conduct unprotected. In that circum-
stance, the court can proceed with the suit, without breaking
new legal ground on the scope of the right to strike.
In all events, then, courts can properly decide the Garmon
issue without making law in this area, precisely as Congress
intended. Indeed, I think we best respect congressional
intent regarding the Board's authority to develop uniform
5
Justice Blackmun warned that a formulation of the Garmon test that
directs attention to a party's evidence might lead some courts to make
such an errant assessment, “under the guise of weighing the suffciency of
the evidence.” Longshoremen v. Davis, 476 U. S. 380, 404 (1986) (opinion
concurring in part and dissenting in part) (expressing the concern that a
future court might misunderstand its role and mistakenly undertake “[to]
mak[e] precisely the determination that Garmon makes clear is for the
Board, and only the Board, to make”). That warning was prescient.
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Jackson, J., dissenting
labor law by leav i ng the appl icati on of the Board's
reasonable-precauti
ons principle to the Board itself. The
majority's contrary approach opens up the possibility that
courts around the country will now act on bare allegations
to generate conficting results about the contours of the ven-
erated right to strike, which, ironically, was the primary con-
cern that motivated Congress to create the Board in the
frst place.
IV
For what it's worth, even if the majority's approach to de-
ciding the Garmon question were the correct one, the major-
ity misapplies the reasonable-precautions principle to the al-
legations here in a manner that threatens to impinge on the
right to strike and on the orderly development of labor law.
A
1
A strike, by defnition, is a “concerted stoppage of work by
employees,” or “any concerted slowdown or other concerted
interruption of operations by employees.” § 142(2). When
employees stop working, production may halt, deliveries may
be delayed, and services may be canceled. At the risk of
stating the obvious, this means that the workers' right to
strike inherently includes the right to impose economic harm
on their employer.
Congress was well aware that organized labor's exercise
of the right to strike risks harm to an employer's economic
interests. See § 151; NLRB v. Erie Resistor Corp., 373 U. S.
221, 234 (1963) (Congress's protection of the right to strike
refects its understanding that strikes are authorized “eco-
nomic weapon[s]”). Yet, Congress protected that right any-
way. In fact, the threat of economic harm posed by the
right to strike is a feature, not a bug, of the NLRA. The
potential pain of a work stoppage is a powerful tool, and
one that unquestionably advances Congress's codifed goal of
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achieving “equality of bargaining power between employers
and
employees.” § 151. Unions leverage a strike's eco-
nomic harm (or the threat of it) into bargaining power, and
then wield that power to demand improvement of employees'
wages and working conditions—goals that, according to Con-
gress, beneft the economy writ large. See Sears, Roe-
buck & Co., 436 U. S., at 190.
Still, the right to strike is, of course, not unlimited. But
when “Congress chose to qualify the use of the strike, it did
so by prescribing the limits and conditions of the abridgment
in exacting detail.” Erie Resistor, 373 U. S., at 234. Sec-
tion 8 enumerates several limitations. For example, a union
must notify an employer that it intends to terminate or mod-
ify its contract—and thus that a strike is possible—at least
60 days before striking. § 158(d). A union cannot strike for
unlawful purposes, such as putting economic pressure on
parties other than the primary employer. § 158(b)(4)(i)(B).
And, in certain healthcare settings, unions must provide at
least 10 days' notice of the precise date and time of a
strike. § 158(g).
Additionally, § 163 of the NLRA (which Congress added
via the 1947 Taft-Hartley Amendments, 61 Stat. 151) states
that “[n]othing in this subchapter, except as specifcally pro-
vided for herein, shall be construed so as either to interfere
with or impede or diminish in any way the right to strike, or
to affect the limitations or qualifcations on that right.”
Thus, the text of the NLRA allows for only two kinds of
limitations on the right to strike: those enumerated in the
Act itself, and the “limitations or qualifcations” on the right
that existed when the Taft-Hartley Amendments were
enacted. See NLRB v. Drivers, 362 U. S. 274, 281–282
(1960). The only relevant limitation here is the one set out
in NLRB v. Fansteel Metallurgical Corp., 306 U. S. 240
(1939).
6
6
The Senate Report accompanying the Taft-Hartley Amendments ex-
plained the four kinds of pre-existing “limitations or qualifcations” on the
right to strike that Congress had in mind in § 163, which were drawn from
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Jackson, J., dissenting
Our Fansteel decision stands for the principle that “em-
ployees
ha[ve] the right to strike but they ha[ve] no license
to commit acts of violence or to seize their employer's plant.”
Id., at 253. The facts of that case involved 95 striking em-
ployees who effected a “sit-down strike by taking over and
holding two of [their employer's] key buildings.” Id., at 248
(internal quotation marks omitted). The employees subse-
quently engaged in “a pitched battle” in which they “resisted
the attempt by the sheriff to evict and arrest them.” Id.,
at 249. We held that the NLRA did not condone this con-
duct, which would “put a premium on resort to force” and
would “subvert the principles of law and order which lie at
the foundations of society.” Id., at 253.
Congress's incorporation of Fansteel's limitation into the
NLRA establishes that, while employees have the right to
withhold their labor peaceably, subsequent affrmative acts
of violence, or seizure of an employer's premises, are not pro-
tected labor practices.
2
As a general matter, the dispute in this case is over
whether employees can withhold their labor if doing so risks
damage to their employer's property. As explained above,
by carefully restricting limitations on the right to strike in
the NLRA itself, Congress has indicated that the act of
peacefully walking off the job is protected strike conduct
even if economic harm incidentally results. What is not pro-
tected is any subsequent affrmative step to destroy or seize
the employer's property. This is the statutory backdrop
against which the Board has developed the narrow require-
ment that striking employees must take reasonable pre-
cautions before or when they strike in order to forestall or
address foreseeable, imminent, and aggravated injury to
decisions of the Board and this Court. See S. Rep. No. 105, 80th Cong.,
1st Sess., 28 (1947); Drivers, 362 U. S., at 281–282. The three other excep-
tions concern strikes for illegal objectives, strikes in breach of contract,
and strikes in breach of other federal law. See S. Rep. No. 105, at 28.
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persons, premises, and equipment that might otherwise be
caused
by their sudden cessation of work.
The Board frst applied this “reasonable precautions” prin-
ciple to rank-and-fle employees in Marshall Car Wheel &
Foundry Co., 107 N. L. R. B. 314, 315 (1953), enf. denied on
other grounds, 218 F. 2d 409 (CA5 1955). There, em-
ployees at a foundry walked off the job at a time when the
foundry's furnace was full of hot molten iron, threatening
severe damage to the employer's plant and equipment. 107
N. L. R. B., at 315. The Board concluded that the employ-
ees' strike conduct was not protected by the NLRA, because
the employees had a “duty to take reasonable precautions to
protect the employer's physical plant from such imminent
damage as for[e]seeably would result from their sudden ces-
sation of work.” Ibid.
The Board has also applied this principle in other similar
cases. It determined, for example, that strikers who walked
out of a certain kind of chemical plant—a plant that handled
“extremely hazardous” chemicals that were “a hazard not
only to employees but also to individuals living in the vicin-
ity”—without shutting down the equipment had engaged in
unprotec ted conduc t. Gene ra l Ch emi ca l Co r p., 290
N. L. R. B. 76, 77, 83 (1988). Similarly, the Board held that
the strike conduct of security guards whose walkout exposed
a federal building 's occupants to “imminent” danger was not
protected by the NLRA. International Protective Servs.,
Inc., 339 N. L. R. B. 701, 703 (2003).
But the narrow duty that Marshall Car Wheel and its
progeny impose does not—and cannot—displace the general
rule that labor strikes are protected even when the workers'
withdrawal of their labor inficts economic harm on the em-
ployer. So the Board has also repeatedly held that employ-
ees have no duty to prevent the loss of perishable goods
caused by their sudden cessation of work.
In a leading case, employees at a raw poultry plant decided
to walk out at 8 a.m. “because by that time all employees
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Jackson, J., dissenting
would have reported to work and [the employer] would be in
fu
ll operation with its largest number of chickens on the
line.” Lumbee Farms Coop., Inc., 285 N. L. R. B. 497, 503
(1987). The Board affrmed the ALJ's reasoning that “[t]he
fact that the strike occurred during the workday when chick-
ens were on the line and vulnerable to loss does not mean
employees automatically lost protection under the Act,” be-
cause “[s]trikers are not required under the Act to institute
the strike at a specifc time of day.” Id., at 506. Indeed, it
is “[n]orma[l]” for “planned employee strikes [to be] timed to
ensure the greatest impact on an employer.” Ibid.
The Board has applied this same reasoning in cases involv-
ing, for example, cheese and milk. See Leprino Cheese Co.,
170 N. L. R. B. 601, 605 (1968); Central Okla. Milk Producers
Assn., 125 N. L. R. B. 419, 435 (1959). In those cases, the
Board also explained that the reasonable-precautions prin-
ciple is “limited to situations involving a danger of `ag-
gravated' injury to persons or premises”—a danger “[o]b-
viously” not posed by the loss of, for example, cheese.
Leprino Cheese, 170 N. L. R. B., at 607 (emphasis added).
The Board has consistently reiterated that “loss is not un-
common when a strike occurs.” Central Okla. Milk Pro-
ducers, 125 N. L. R. B., at 435.
In short, it is indisputable that workers have a statutory
right to strike despite the fact that exercising that right
risks economic harm to employers. Congress has, in effect,
drawn a line between those economic harms that are inher-
ent in the act of peacefully walking off the job (which do not
render the strike unprotected) and those that result from
workers taking subsequent affrmative steps to seize the em-
ployer's premises or engage in acts of violence (strike con-
duct that is not protected by the NLRA). The Board has
further recognized a narrow duty that arises if a sudden ces-
sation of work risks foreseeable, imminent, and aggravated
harm to persons, premises, or equipment. Beyond this nar-
row reasonable-precautions requirement, however, employ-
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ees have no obligation to protect their employer's economic
i
nterests when they exercise the right to withhold their
labor.
B
Glacier does not allege that the cement truckdrivers com-
mitted acts of violence or seized its plant or property as part
of the strike the Union orchestrated. Instead, the thrust of
its complaint is that the Union was aware of “the perishable
nature of batched concrete,” App. 9, and that the drivers'
walkout was intentionally timed so as to risk harm to that
product. See id., at 10 (alleging “sabotage, ruination and
destruction of Glacier's batched concrete”).
I agree with the majority that the risk of losing the
batched concrete alone would not be suffcient to divest the
striking drivers of statutory protection. As Glacier ac-
knowledges, wet concrete is a perishable good. Ibid. And
the Board has repeatedly reaffrmed that the loss of such
perishable goods due to a mere work stoppage does not ren-
der a strike unprotected.
There is also no duty to take reasonable precautions to
prevent this kind of economic loss, which—standing alone—
posed no risk to persons, premises, or equipment, let alone a
risk of aggravated harm. While it seems that the drivers
were in a position to save the batched concrete that was
inside their trucks when the strike was called (by, for in-
stance, continuing to deliver it to the intended customers),
that is beside the point. Employees have a protected right
to withhold their labor. And it would undercut that right if
they could be held liable for the incidental loss of the perish-
able goods (which includes concrete no less than raw poultry,
cheese, or milk) that they tend to as part of their job.
7
7
Justice Alito, relying on the rule from NLRB v. Fansteel Metallur-
gical Corp., 306 U. S. 240 (1939), gleans more from the loss of concrete
than either the majority or I do. He concludes that the NLRA's right to
strike does not protect the drivers' alleged conduct because Glacier has
alleged that the drivers purposefully caused the batched concrete to be
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Jackson, J., dissenting
Where I disagree with the majority is the conclusion it
draws
from the fact that the batched concrete also risked
harm to the drivers' trucks, at least as alleged in Glacier's
complaint. The majority repeatedly ties the loss of the con-
crete—in particular, the risk that it would harden in the
trucks—to the alleged risk of harm to the delivery trucks
themselves.
8
But, to me, the alleged risk of harm to Gla-
cier's trucks involves a relatively complex factual analysis
under the Board's reasonable-precautions principle.
Glacier alleges that, “[o]nce at rest, concrete begins hard-
ening immediately, and depending on the mix can begin to
set within 20 to 30 minutes.” Id., at 8. Its complaint also
asserts that “[i]f batched concrete remains in the revolving
drum of the ready-mix truck beyond its useful life span, the
batched concrete is certain or substantially certain to harden
in the revolving drum and cause signifcant damage to the
concrete ready-mix truck.” Id., at 9. But Glacier's own
submissions in Washington state court suggest that the
Union instructed the drivers to return their trucks to Gla-
cier's yard after the strike began and to keep the ready-mix
destroyed. In my view, that approach fails to appreciate the distinction
Fansteel drew between purposefully but peacefully stopping work (and
the economic consequences that fow from that decision), which is pro-
tected, and taking subsequent, affrmative steps of violence or property
seizure, which is unprotected. To be sure, Fansteel would have rendered
the drivers' actions here patently unprotected if they had taken the af-
frmative steps of stealing the trucks, slashing the trucks' tires, or dump-
ing out the concrete after they went on strike. But nothing like that is
alleged in Glacier's complaint.
8
See, e. g., ante, at 781 (“[T]he Union executed the strike in a manner
designed to compromise the safety of Glacier's trucks and destroy its con-
crete”); ante, at 783 (“[The drivers] not only destroyed the concrete but
also put Glacier's trucks in harm's way. This case therefore involves
much more than `a work stoppage at a time when the loss of perishable
products is foreseeable' ”); ante, at 785 (“The Union's actions not only re-
sulted in the destruction of all the concrete Glacier had prepared that day;
they also posed a risk of foreseeable, aggravated, and imminent harm to
Glacier's trucks”).
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Jackson, J., dissenting
trucks running. See id., at 34, 77. Glacier's submissions
a
lso suggest that those precautions actually provided the
company's managers and nonstriking employees with suff-
cient time to decide how to address the situation to prevent
any harm to the trucks. See id., at 13, 72, 77, 82–83.
Was any risk of harm to the trucks here “imminent,” given
the allegation that the Union instructed the drivers to keep
the trucks running? Is the risk of concrete hardening in a
delivery truck “aggravated,” in the way Marshall Car Wheel
contemplates? Was returning the trucks to the employer's
premises and leaving them running a suffcient “reasonable”
precaution, because it gave the employer suffcient time to
address any risk of harm? Making the call about whether
the NLRA protects the Union's conduct raises these ques-
tions and others. Importantly, these kinds of questions
not only involve making nuanced factual distinctions but
also demonstrate that applying the Board's reasonable-
precautions precedents is, at bottom, a line-drawing exercise.
Under circumstances like these, a court can confdently de-
clare that a union's conduct is not even arguably protected
for Garmon purposes only where the allegations make out a
clear Fansteel claim or where the alleged facts implicate a
reasonable-precautions case that is directly on point. Be-
cause neither is true here, the Court should have concluded
that the Union's conduct was at least arguably protected.
Even if the Court's task under Garmon were to apply the
Board's reasonable-precautions principle to the allegations of
Glacier's complaint and decide whether or not the Union en-
gaged in unprotected conduct (to reiterate: that is not the
assignment, see Part III–A, supra), I cannot agree with the
majority's conclusion that the risk to the trucks rendered the
drivers' strike unprotected by the NLRA. Instead, I would
have credited Glacier's own account, and thus would have
concluded that the Union took reasonable precautions when
it instructed the drivers to return the trucks and leave them
running to avoid the concrete hardening imminently in the
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Cite
as: 598 U. S. 771 (2023)
813
Jackson, J., dissenting
drums. The majority reaches the opposite conclusion by
g
iving far too little weight to the allegation that the drivers
returned the trucks, and also by substantially discounting
the allegations that support the Union's claim that the driv-
ers left their trucks and revolving drums running. See
ante, at 784.
Fortunately, the pending Board determination of what ac-
tually happened in connection with this particular strike will
establish—as a matter of fact and not mere allegation—what
precautions (if any) the drivers actually took and what harm
(if any) the Union's conduct actually posed to Glacier's
trucks.
9
But our different takes on these allegations only
underscore the potential for variable outcomes when courts
apply the Board's fac t-dependent pr i nciples to bare
assertions.
To the extent that the majority's conclusion rests on the
alleged fact that “by reporting for duty and pretending as if
they would deliver the concrete, the drivers prompted the
creation of the perishable product” that “put Glacier's trucks
in harm's way,” ante, at 783, I see nothing aggravated or
even untoward about that conduct. Glacier is a concrete-
delivery company whose drivers are responsible for deliver-
ing wet concrete, so it is unremarkable that the drivers
struck at a time when there was concrete in the trucks.
While selling perishable products may be risky business, the
perishable nature of Glacier's concrete did not impose some
obligation on the drivers to strike in the middle of the night
or before the next day's jobs had started. To the contrary,
it was entirely lawful for the drivers to start their workday
per usual, and for the Union to time the strike to put “maxi-
mum pressure on the employer at minimum economic cost to
the union.” NLRB v. Insurance Agents, 361 U. S. 477, 496
(1960); see also Lumbee Farms Coop., 285 N. L. R. B., at 506.
9
For the same reason, the state court would not be bound by the majori-
ty's recitation of the facts at this motion-to-dismiss stage in any future
proceedings on this matter in state court.

814 GLA
CIER NORTHWEST, INC. v. TEAMSTERS
Jackson, J., dissenting
Nor was the onus of protecting Glacier's economic inter-
ests
if a strike was called in the middle of the day on the
drivers—it was, instead, on Glacier, which could have taken
any number of prophylactic, mitigating measures.
10
What
Glacier seeks to do here is to shift the duty of protecting an
employer's property from damage or loss incident to a strike
onto the striking workers, beyond what the Board has al-
ready permitted via the reasonable-precautions principle.
In my view, doing that places a signifcant burden on the
employees' exercise of their statutory right to strike, unjust-
ifably undermining Congress's intent. Workers are not in-
dentured servants, bound to continue laboring until any
planned work stoppage would be as painless as possible for
their master. They are employees whose collective and
peaceful decision to withhold their labor is protected by the
NLRA even if economic injury results.
***
Today, the majority fails, in multiple respects, to heed Con-
gress's intent with respect to the Board's primary role in
adjudicating labor disputes, despite ostensibly applying Gar-
mon, the bedrock case on that issue. The Court's ruling is
likely to cause considerable confusion among the lower
courts about what Garmon requires. And any such confu-
sion not only threatens to encroach upon the Board's prerog-
atives, as Congress has assigned them, but also risks erosion
of the right to strike.
Yet, the posture of this case provides an opportunity to
mitigate the results of the majority's errors. On remand,
10
For example, Glacier could have instituted a lockout, see American
Ship Building Co. v. NLRB, 380 U. S. 300, 310 (1965), used nonstriking
employees to deliver the batched concrete, or had temporary replacement
drivers lined up and ready to go. Glacier was on notice that a strike was
possible because the Union was statutorily required to give 60-days ad-
vance notice of the proposed termination or modifcation of the collective-
bargaining agreement, § 158(d), and because negotiations had broken
down.
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815
Jackson, J., dissenting
the state court should dismiss Glacier's complaint without
pre
judice or stay its proceedings in view of the General
Counsel's complaint. Meanwhile, the Board—which is not
bound by the allegations in Glacier's complaint when making
its assessment, and is well equipped to make fndings of fact
concerning the strike conduct at issue—should proceed to
determine whether Glacier has interfered with strike con-
duct that is protected by the NLRA, as alleged by the Gen-
eral Counsel.
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Reporter’s Note
The attached opinion has been revised to refect the usual publication
and citation style of the United States Reports. The revised pagination
makes available the offcial United States Reports citation in advance of
publication. The syllabus has been prepared by the Reporter of Decisions
for the convenience of the reader and constitutes no part of the opinion of
the Court. A list of counsel who argued or fled briefs in this case, and
who were members of the bar of this Court at the time this case was
argued, has been inserted following the syllabus. Other revisions may
include adjustments to formatting, captions, citation form, and any errant
punctuation. The following additional edits were made:
p. 798, line 10, “12” is changed to “11”