Berk v. Choy

P R E L I M I N A R Y P R I N T
Volume 607 U. S. Part 1
Pages 187–212
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T H E S U P R E M E C O U R T
January 20, 2026
REBECCA A. WOMELDORF
reporter of decisions
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TERM, 2025
187
Syllabus
BERK v. CHOY et al.
certiorari
to the united states court of appeals for
the third circuit
No. 24–440. Argued October 6, 2025—Decided January 20, 2026
Delaware law provides that a plaintiff may not sue for medical malpractice
unless a medical professional attests to the suit's merit in an “affdavit
of merit” that “accompanie[s]” the plaintiff 's complaint. Del. Code, Tit.
18, § 6853(a)(1). Petitioner Harold Berk sued Dr. Wilson Choy and
Beebe Medical Center in federal court for medical malpractice under
Delaware law, but failed to provide the affdavit required by § 6853.
Berk argued that § 6853 is not enforceable in federal court because it is
displaced by the Federal Rules of Civil Procedure. The District Court
dismissed Berk's lawsuit for failure to comply with Delaware's affdavit
law. The Third Circuit affrmed.
Held: Delaware's affdavit law does not apply in federal court. Pp. 191–200.
(a) When a plaintiff brings a state-law claim in federal court, the
court faces a choice-of-law problem: whether to apply state or federal
law. The Rules of Decision Act directs federal courts to apply state
substantive law unless the Constitution, a treaty, or a statute otherwise
requires or provides. 28 U. S. C. § 1652. The Rules Enabling Act,
which authorizes the Supreme Court to adopt uniform rules of proce-
dure for district courts, provides for the application of federal law.
§ 2072(a). So, when a valid Federal Rule of Civil Procedure is on point,
it displaces contrary state law even if the state law would qualify as
substantive under Erie R. Co. v. Tompkins, 304 U. S. 64. The analysis
is straightforward: The Court frst asks whether a Federal Rule answers
the disputed question. If a Federal Rule does, it governs, unless it
“exceeds statutory authorization or Congress's rulemaking power.”
Shady Grove Orthopedic Associates, P. A. v. Allstate Ins. Co., 559 U. S.
393, 398. Pp. 191–192.
(b) Here, Rule 8 answers the disputed question whether Berk's law-
suit may be dismissed because his complaint was not accompanied by an
affdavit. Rule 8 prescribes the information a plaintiff must present
about the merits of his claim at the outset of litigation: “a short and
plain statement of the claim showing that [he] is entitled to relief.”
Fed. Rule Civ. Proc. 8(a)(2). By requiring no more than a statement of
the claim, Rule 8 establishes “implicitly, but with unmistakable clarity,”
Hanna v. Plumer, 380 U. S. 460, 470, that evidence of the claim is not
required. Rule 12 reinforces the point by providing only one ground

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188 BERK
v. CHOY
Syllabus
for dismissal based on the merits—“failure to state a claim upon which
rel
ief can be granted,” Rule 12(b)(6)—and prohibiting courts from con-
sidering “matters outside the pleadings” when evaluating whether a
plaintiff has stated a claim, Rule 12(d). The court instead asks only
whether the complaint's factual allegations, if taken as true, “state a
claim to relief that is plausible on its face.” Bell Atlantic Corp. v.
Twombly, 550 U. S. 544, 570. Lower federal courts have sometimes
tried to demand more information than Rule 8 requires for certain kinds
of claims. This Court has consistently rejected such efforts. Dela-
ware's law and Rule 8 thus give different answers to the question
whether Berk's complaint can be dismissed as insuffcient because it was
unaccompanied by an affdavit.
Defendants offer a workaround: They rewrite Delaware's law. After
defendants' edits, the Delaware law is no longer a pleading requirement
but a free-foating evidentiary requirement that can serve as the basis
for an early dismissal. But that requirement could not be enforced
under the Federal Rules. Defendants concede that the absence of an
affdavit is not grounds for dismissal under Rule 12(b)(6). And Rule 56
already prescribes the mechanism for putting a plaintiff to his proof: a
motion for summary judgment.
Finally, defendants' argument that Rule 11's proviso concerning affi-
davits incorporates state affdavit laws like § 6853 fails because the pro-
viso cannot be read to address affdavits from third parties. Pp. 192–198.
(c) Because Rule 8 and § 6853 answer the same question, Rule 8 gov-
erns so long as it is valid under the Rules Enabling Act, which requires
that Federal Rules be procedural rather than substantive. 28 U. S. C.
§ 2072(b). Rule 8 is valid under the Rules Enabling Act because it
“really regulates procedure.” Sibbach v. Wilson & Co., 312 U. S. 1, 14.
Defendants argue that determining whether a Rule is valid under the
Rules Enabling Act requires also asking whether the displaced state
law is substantive, but “the substantive nature of [a state] law, or its
substantive purpose, makes no difference” to the analysis of a Federal
Rule's validity. Shady Grove, 559 U. S., at 409. Pp. 198–200.
Reversed and remanded.
Barrett, J., delivered the opinion of the Court, in which Roberts,
C. J., and Thomas, Alito, Sotomayor, Kagan, Gorsuch, and Kava-
naugh, JJ., joined. Jackson, J., fled an opinion concurring in the judg-
ment, post, p. 200.
Andrew T. Tutt argued the cause for petitioner. With him
on the briefs were R. Stanton Jones, Anthony J. Franze,
Kolya D. Glick, Samuel I. Ferenc, and Dana Kagan McGinley.

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189
Opinion of the Court
Frederick R. Yarger argued the cause for respondent Wil-
son
C. Choy, M.D. With him on the brief were Michael L.
O'Donnell, Kevin D. Homiak, William P. Sowers, Rebecca
Graves Payne, John A. Elzufon, and Nathan V. Gin. Sarah
E. Harrington fled a brief for respondent Beebe Medical
Center, Inc. With her on the brief were David M. Zionts,
Kendall T. Burchard, and John J. Hare.*
Justice Barrett delivered the opinion of the Court.
The cost of malpractice insurance for doctors and hospitals
has signifcantly increased in some areas of the country. In
response, several States have imposed a screening mecha-
nism on malpractice suits, requiring plaintiffs to submit an
affdavit from a medical professional attesting to the suit's
*Briefs of amici curiae urging reversal were fled for the American
Association for Justice by Robert S. Peck and Jeffrey R. White; for Civil
Procedure Professors by Alan B. Morrison; for Public Justice by John J.
Korzen and Leah M. Nicholls; and for the Hon. Mark W. Bennett et al. by
D. Chanslor Gallenstein.
Briefs of amici curiae urging affrmance were fled for the State of
Tennessee et al. by Jonathan Skrmetti, Attorney General of Tennessee,
J. Matthew Rice, Solicitor General, and Harrison Gray Kilgore, Senior
Assistant Attorney General, and by the Attorneys General for their re-
spective States as follows: Steve Marshall of Alabama, Tim Griffn of
Arkansas, Philip J. Weiser of Colorado, James Uthmeier of Florida, Chris
Carr of Georgia, Raúl Labrador of Idaho, Theodore E. Rokita of Indiana,
Brenna Bird of Iowa, Kris W. Kobach of Kansas, Russell Coleman of
Kentucky, Liz Murrill of Louisiana, Keith Ellison of Minnesota, Lynn
Fitch of Mississippi, Andrew Bailey of Missouri, Michael T. Hilgers of
Nebraska, Matthew J. Platkin of New Jersey, Drew H. Wrigley of North
Dakota, Dave Yost of Ohio, David W. Sunday, Jr., of Pennsylvania, Alan
Wilson of South Carolina, Marty Jackley of South Dakota, Ken Paxton of
Texas, Derek Brown of Utah, Charity R. Clark of Vermont, Jason Miy-
ares of Virginia, and John B. McCuskey of West Virginia; for the American
Hospital Association et al. by Colleen E. Roh Sinzdak; for the American
Medical Association et al. by Jack R. Bierig; for the DRI Center for Law
and Public Policy by Hillary A. Taylor; for Insurance Companies et al. by
Kendra N. Beckwith and Michael D. Miller; and for Michael T. Morley by
Richard A. Simpson and F. Andrew Hessick.

190 BERK
v. CHOY
Opinion of the Court
merit. We consider whether Delaware's affdavit require-
ment
applies in federal court and hold that it does not.
I
While on a trip to Delaware, Harold Berk fell out of bed.
According to his complaint, he was taken by ambulance to a
hospital owned by Beebe Medical Center, Inc., where an X
ray revealed a fractured ankle. Dr. Wilson Choy recom-
mended that Berk be ftted with a protective boot.
The ftting did not go well. Hospital employees forced
Berk's leg into the boot, twisting his fractured ankle. Still,
Dr. Choy did not immediately order another X ray; he told
Berk to keep weight off his ankle, proposed a follow-up ap-
pointment in two weeks, and sent Berk on his way. At the
follow-up, Berk got a second X ray, which showed that his
ankle was not just fractured but also severely deformed, re-
quiring surgery.
Berk sued Beebe Medical Center and Dr. Choy (whom we
will call defendants) for medical malpractice under Delaware
law. Because Berk and defendants are citizens of different
States, Berk could sue in federal court based on diversity
jurisdiction.
Under Delaware law, a plaintiff may not sue for medical
malpractice unless an affdavit of merit “accompanie[s]” the
complaint. Del. Code, Tit. 18, § 6853(a)(1) (2025). The aff-
davit must be signed by a medical professional, § 6853(c), and
it must state that there are “reasonable grounds to believe
that there has been health-care medical negligence com-
mitted by each defendant,” § 6853(a)(1). A plaintiff with
“good cause” may secure a single 60-day extension of time in
which to fle the affdavit, ibid., but he must fle the extension
motion before or when he fles the complaint, § 6853(a)(2). If
an affdavit does not accompany the complaint and the plain-
tiff has not fled a timely extension motion, then the clerk of
court shall “refuse to fle the complaint and it shall not be
docketed.” § 6853(a)(1). The defendants need not take any
action with respect to the complaint until 20 days after the
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affdavit of merit is fled. § 6853(a)(4). Upon the defend-
ants'
motion, the court must determine in camera if the af-
fdavit satisfes the statutory requirements. § 6853(d).
Attempting to comply with § 6853, Berk immediately
moved for an extension of time to fle an affdavit. The Dis-
trict Court granted Berk's motion, and Berk tried to track
down a doctor willing to provide an affdavit (an ordeal
spawning separate litigation). But the clock ran out, and
coming up empty-handed, Berk instead fled his medical rec-
ords under seal. Defendants moved the District Court to
review Berk's submissions in camera to determine whether
they complied with § 6853. Berk countered that § 6853 is not
enforceable in federal court because it is displaced by the
Federal Rules of Civil Procedure. The District Court dis-
agreed with Berk and dismissed his lawsuit for failure
to comply with Delaware's affdavit law. See 2023 WL
2770573, *1–*2 (D Del., Apr. 4, 2023).
The Third Circuit affrmed, holding that § 6853 applies in
federal court. See 2024 WL 3534482, *4 (July 25, 2024).
The court concluded that the Federal Rules of Civil Proce-
dure are silent as to whether an affdavit must accompany
the complaint. Id., at *2–*3. Where the Federal Rules are
silent, state law applies if it is substantive. See Erie R. Co.
v. Tompkins, 304 U. S. 64, 78 (1938). A state law is sub-
stantive if (1) it is outcome determinative, and (2) failing to
apply it in federal court would promote forum shopping and
the inequitable administration of the law. See Hanna v.
Plumer, 380 U. S. 460, 467–469 (1965). After applying this
test, the Third Circuit concluded that § 6853 is substantive
and affrmed the dismissal of Berk's suit. See 2024 WL
3534482, *3–*4.
We granted certiorari. 604 U. S. 1193 (2025).
II
State-law claims are usually brought in state court. But
if the parties are citizens of different States and the amount
in controversy exceeds a certain threshold, a plaintiff may
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192 BERK
v. CHOY
Opinion of the Court
choose to sue in federal court. 28 U. S. C. § 1332. In that
e
vent, the federa l cour t faces a choice-of-law problem:
whether to apply state or federal law. The Rules of Deci-
sion Act directs federal courts to apply state substantive law,
leaving federal law to cover the rest. § 1652. Following
that direction is harder than it looks, because determining
whether a state law is substantive requires a court to enter
“Erie's murky waters.” Shady Grove Orthopedic Associ-
ates, P. A. v. Allstate Ins. Co., 559 U. S. 393, 398 (2010).
Yet when a Federal Rule of Civil Procedure is on point,
a federal court bypasses Erie's inquiry altogether. That is
because the Rules of Decision Act dictates that state sub-
stantive law must yield if the Constitution, a treaty, or a
statute “otherwise require[s] or provide[s].” § 1652. And
the Rules Enabling Act, which authorizes the Supreme
Court to adopt uniform rules of procedure for district courts,
provides for the application of federal law. § 2072(a); see
also Fed. Rule Civ. Proc. 1 (“These rules govern the proce-
dure in all civil actions and proceedings in the United States
district courts . . . ”). Thus, a valid Rule of Civil Procedure
displaces contrary state law even if the state law would qual-
ify as substantive under Erie's test. See Hanna, 380 U. S.,
at 469–474.
Analyzing whether a Federal Rule displaces state law is
straightforward. We frst ask whether the Federal Rule
“answers the question in dispute.” Shady Grove, 559 U. S.,
at 398. In doing so, we interpret the Federal Rules the
same way we interpret federal laws more generally: by giv-
ing them their “plain meaning.” Walker v. Armco Steel
Corp., 446 U. S. 740, 750, n. 9 (1980). If a Federal Rule an-
swers the disputed question, it governs, unless it “exceeds
statutory authorization or Congress's rulemaking power.”
Shady Grove, 559 U. S., at 398.
A
In this case, the disputed question is whether Berk's law-
suit may be dismissed because his complaint was not accom-

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Opinion of the Court
panied by an expert affdavit.
1
Ru
le 8 gives the answer. It
prescribes the information a plaintiff must present about the
merits of his claim at the outset of litigation: “a short and
plain statement of the claim showing that [he] is entitled to
relief.” Fed. Rule Civ. Proc. 8(a)(2). By requiring no more
than a statement of the claim, Rule 8 establishes “implicitly,
but with unmistakable clarity,” Hanna, 380 U. S., at 470, that
evidence of the claim is not required. Cf. Burlington North-
ern R. Co. v. Woods, 480 U. S. 1, 7–8 (1987) (declining to apply
a state statute where a Federal Rule “occupies the statute's
feld of operation”).
Rule 12 reinforces the point. It provides only one ground
for dismissal based on the merits: “failure to state a claim
upon wh ich rel ief can be granted. ” Fed. Ru le Civ.
Proc. 12(b)(6). When evaluating whether a plaintiff has
stated a claim, the court cannot consider “matters out-
side the pleadings.” Rule 12(d). The court instead asks
only whether the complaint's factual allegations, if taken
as true, “state a claim to relief that is plausible on its
face.” Bell Atlantic Corp. v. Twombly, 550 U. S. 544, 570
(2007). A complaint that satisfes this standard is “well-
pleaded” and “may proceed even if it strikes a savvy judge
that actual proof of the facts alleged is improbable.” Id.,
at 556.
1
The concurrence objects to our framing the disputed question around
dismissal because doing so “assumes that Berk's lawsuit has already been
. . . fled and docketed.” Post, at 202 (Jackson, J., concurring in judg-
ment). But Berk's lawsuit has already been fled and docketed, see
No. 1:22–cv–01506 (D Del., Nov. 18, 2022), ECF Doc. 1, which is how it
found its way here. The only question in dispute is whether Berk's law-
suit may be dismissed—indeed, that is the question on which we granted
certiorari. See Pet. for Cert. i. The concurrence reframes the question
in dispute as “what is required to start a medical malpractice case.” Post,
at 203. But because no one argues that the court violated § 6853 by dock-
eting Berk's complaint, the concurrence is ultimately forced to grapple
with the question whether Berk's lawsuit may be “dismiss[ed].” Post, at
209. By focusing on dismissal from the start, we do not “jum[p] the gun,”
post, at 202, but rather cut to the chase.
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By design, this system of pleading makes it relatively easy
for
plaintiffs to subject defendants to discovery—even for
claims that are likely to fail. To protect defendants from
this burden, lower federal courts have sometimes tried to
require more information for certain kinds of claims: 42
U. S. C. § 1983 actions against municipalities, Leatherman v.
Tarrant County Narcotics Intelligence and Coordination
Unit, 507 U. S. 163 (1993); employment discrimination suits,
Swierkiewicz v. Sorema N. A., 534 U. S. 506 (2002); and pris-
oner suits, Jones v. Bock, 549 U. S. 199 (2007). We have con-
sistently rejected such efforts. As we explained in Leather-
m an—wh ich dea lt w ith a demand that plai nti ffs plead
certain § 1983 claims with added specifcity—Rule 8(a)(2) re-
quires “only” a “ `short and plain statement of the claim.' ”
507 U. S., at 165, 168 (quoting Rule 8(a)(2)). Unless the Fed-
eral Rules single out a claim for special treatment, see, e. g.,
Fed. Rule Civ. Proc. 9, Rule 8 sets a ceiling on the informa-
tion that plaintiffs can be required to provide about the mer-
its of their claims.
Delaware's affdavit requirement is at odds with Rule 8
because it demands more: A medical malpractice suit cannot
proceed “unless the complaint is accompanied by . . . [a]n
affdavit of merit.” § 6853(a)(1). Under Rule 8, factual alle-
gations are suffcient, but under the Delaware law, the plain-
tiff needs evidence too. See Dishmon v. Fucci, 32 A. 3d 338,
344 (Del. 2011) (describing § 6853 as imposing a “prima facie
evidentiary requiremen[t]”); see also Brief for Respondent
Beebe 23 (same). The two rules thus give different answers
to the question whether Berk's complaint can be dismissed
as insuffcient because it was unaccompanied by an affdavit.
It is true, as defendants and the concurrence are quick to
point out, that an affdavit of merit is a document separate
from the “pleading,” and that, by its literal terms, Rule 8
defnes only what the “pleading . . . must contain.” But we
think it is fair to infer that by specifying what information
about the merits is required in the “pleading,” Rule 8 ex-
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cludes the possibility of requiring even more information on
the
same topic—whether in the “pleading ” itself or on a sep-
arate sheet of paper attached to it. Cf. Jones, 549 U. S., at
205, 212–217 (rejecting requirement that prisoners “attach
proof of exhaustion . . . to their complaints” as inconsistent
with Rule 8). Rule 8 addresses what information a plaintiff
must provide about the merits of his claim at the outset of
litigation. Section 6853 addresses the same issue—and in
doing so, imposes a different standard.
2
Resisting this conclusion, defendants cite Cohen v. Benef-
cial Industrial Loan Corp., 337 U. S. 541 (1949), for the
broad proposition that all state “preconditions to proceed-
ing ” are consistent with the Federal Rules. Brief for Re-
spondent Beebe 26–27; see Brief for Respondent Choy 20–
21. They substantially overread Cohen. There, a state law
rendered an unsuccessful plaintiff in a shareholder derivative
suit liable for all the defendant's expenses, including attor-
ney's fees, and as security for that potential liability, required
the plaintiff to post a bond before proceeding with the action.
337 U. S., at 543. The plaintiffs argued that the bond re-
quirement was displaced by then-Rule 23, which governed
shareholder derivative suits in federal court. Id., at 556.
2
The concurrence accuses us—and the “many Courts of Appeals” that
agree with us—of “contorting ” Rule 8 by reading it to implicitly preclude
courts from requiring plaintiffs to provide additional information. Post,
at 208, and n. 6. Yet drawing a negative inference from text is sometimes
the best way to understand it. See A. Scalia & B. Garner, Reading Law:
The Interpretation of Legal Texts 107–111 (2012) (negative-implication
canon). And while the concurrence criticizes the negative inference we
draw as “inattentively capacious,” post, at 206, its Rule 3 analysis depends
on an analogous inference. Rule 3 establishes what happens once a com-
plaint is fled: “A civil action is commenced by fling a complaint with the
court.” Fed. Rule Civ. Proc. 3. Section 6853, meanwhile, establishes
what is required “to fle the complaint . . . with the court”: an affdavit
of merit or an extension motion. § 6853(a)(1). The concurrence fnds a
collision only by reading Rule 3 to implicitly foreclose any precondition
to fling the complaint. So if a negative inference is a “contortion,” the
concurrence's argument fails by its own measure.

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Cohen held that there was no confict because the state law
and
Rule 23 addressed different issues: The state law created
a liability, while Rule 23 dealt with “disclosure to the court
and notice to the parties in interest.” Id., at 555–556.
Cohen thus did not identify and exempt a broad category
of so-called preconditions to proceeding from confict with
the Federal Rules. It held that a particular state law ad-
dressed a matter that was unaddressed by the relevant Fed-
eral Rule. Here, by contrast, the state law and the Federal
Rule address the same issue: the information that a plaintiff
must provide about the merits of his claim at the outset of
litigation. Describing the affdavit requirement as a “pre-
conditio[n] to proceeding ” does not magically dispel the
confict.
Defendants offer a workaround: They rewrite Delaware's
law. While § 6853 provides that an affdavit must “accom-
pan[y]” the complaint, defendants suggest that the district
court can simply require it “early in [a] case.” Brief for Re-
spondent Beebe 13; see also Brief for Respondent Choy 36
(suggesting affdavit can be fled “weeks” or “months” after
the complaint). This proposal is inspired by § 6853's allow-
ance for an extension of time in which to fle the affdavit.
But defendants treat this exception—which is available only
“for good cause shown”—as the rule and rework the excep-
tion to boot. In federal court, apparently, an extension mo-
tion need not precede or accompany the complaint; nor is the
district court limited to granting one 60-day extension. See,
e. g., Brief for Respondent Beebe 23–25. And defendants'
proposed changes do not stop there: They would also have
us delete the provision that absolves a defendant from “tak-
[ing] any action with respect to the complaint” until the aff-
davit is fled. § 6853(a)(4). Under Federal Rule 12(a)(1),
service of the summons and complaint triggers a defendant's
obligation to respond, and defendants admit that the Federal
Rule controls on this point.

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After defendants' edits, the Delaware law is no longer a
pleadi
ng requirement that serves a gatekeeping function; it
is a free-foating evidentiary requirement that can serve as
the basis for an early dismissal. Yet even were it acceptable
to take creative license with the Delaware law, there would
be no way to enforce such a requirement. Defendants con-
cede that the absence of an affdavit is not grounds for dis-
missal under Rule 12(b)(6). They foat the possibility of dis-
missal for failure to prosecute, but that does not work
because Berk actively participated in the litigation. De-
fendants' frst choice is the course the District Court took
here: dismissal based on the court's inherent authority. The
problem, however, is that the Federal Rules already pre-
scribe a mechanism for putting a plaintiff to his proof: a mo-
tion for summary judgment. See Fed. Rule Civ. Proc. 56.
And that does not offer defendants the protection they want,
because before ruling on the motion, the court must allow
the nonmovant “adequate time for discovery.” Celotex
Corp. v. Catrett, 477 U. S. 317, 322 (1986); see also Rule 12(d)
(requiring a “reasonable opportunity to present all the [per-
tinent] material” if motion to dismiss is converted to motion
for summary judgment). That defendants cannot ft the af-
fdavit requirement into the Federal Rules illustrates that it
has no place there.
Perhaps recognizing this, defendants devote most of their
energy to arguing that the Federal Rules contain a loophole.
According to defendants, a proviso tucked into Rule 11
makes state affdavit laws applicable in federal court even if
they confict with other Federal Rules. Rule 11 provides
that “[u]nless a rule or statute specifcally states otherwise,
a pleading need not be verifed or accompanied by an affda-
vit.” Fed. Rule Civ. Proc. 11(a). Defendants argue that
§ 6853 is a “statute [that] specifcally states otherwise,” ibid.,
and it therefore applies in federal court regardless of
whether it conficts with other Federal Rules.

198 BERK
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Even if Rule 11 incorporates some state affdavit laws, it
does
not incorporate this one. Rule 11 governs the conduct
of those who practice before courts: the “attorney of record”
or the “party personally if the party is unrepresented.”
Ibid. It requires the attorney or pro se party to certify,
after “reasonable” inquiry, that the legal and factual repre-
sentations made to the court are warranted. Rule 11(b).
The sentence on which defendants rely simply “acknowl-
edges” that although Rule 11 generally puts the onus on the
attorney or pro se party to vouch for representations, “in
some situations represented parties are required by rule or
statute to verify pleadings or sign affdavits.” Business
Guides, Inc. v. Chromatic Communications Enterprises,
Inc., 498 U. S. 533, 542 (1991) (emphasis added); see, e. g., Fed.
Rule Civ. Proc. 23.1 (requiring complaints in shareholder de-
rivative actions to be verifed). The sentence has nothing
to do with affdavits from third parties. Accordingly, Rule
11 does not shield Delaware's law from displacement by
Rule 8.
B
Because Rule 8 and § 6853 answer the same question, Rule
8 governs so long as it is valid under the Rules Enabling Act,
which requires that Federal Rules be procedural rather than
substantive. 28 U. S. C. § 2072(b) (“Such rules shall not
abridge, enlarge or modify any substantive right”). The line
between substance and procedure is hazy, and we draw it
differently in different contexts. See Hanna, 380 U. S., at
471 (“The line between `substance' and `procedure' shifts as
the legal context changes”). For purposes of the Rules En-
abling Act, we use a modest test: whether the Federal Rule
“really regulates procedure.” Sibbach v. Wilson & Co., 312
U. S. 1, 14 (1941). Or put differently, “[w]hat matters is
what the Rule itself regulates: If it governs only `the manner
and the means' by which the litigants' rights are `enforced,' it
is valid.” Shady Grove, 559 U. S., at 407 (plurality opinion)
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(quoting Mississippi Publishing Corp. v. Murphree, 326 U. S.
438,
446 (1946)).
In applying this analysis, we have “rejected every statu-
tory challenge to a Federal Rule that has come before us.”
Shady Grove, 559 U. S., at 407 (plurality opinion). We have
upheld Rules governing the certifcation of class actions, id.,
at 408 (Rule 23); see id., at 416, 436 (Stevens, J., concurring
in part and concurring in judgment) (Rule 23); service of
process, Mississippi Publishing Corp., 326 U. S., at 445–446
(Rule 4(f )); compelled mental and physical examinations, Sib-
bach, 312 U. S., at 14–16 (Rule 35); sanctions for frivolous
appeals, Burlington, 480 U. S., at 8 (Rule 38); and sanctions
for signing court papers without reasonably investigating
the facts asserted, Business Guides, 498 U. S., at 551–554
(Rule 11).
Like those Rules, Rule 8 “really regulates procedure.”
Sibbach, 312 U. S., at 14. It determines what plaintiffs must
present to the court about their claims at the outset of litiga-
tion. Although the Rule may have some “practical effect on
the parties' rights,” it regulates “only the process for enforc-
ing those rights,” not “the rights themselves, the available
remedies, or the rules of decision.” Shady Grove, 559 U. S.,
at 407–408 (plurality opinion).
Defendants do not contend otherwise. Instead, they
argue that determining whether a Rule is valid under the
Rules Enabling Act requires asking a second question:
whether the displaced state law is substantive. We rejected
that approach eight decades ago and decline to reconsider it
now. See Sibbach, 312 U. S., at 14. On the contrary, we
underscore that “the substantive nature of [a state] law, or
its substantive purpose, makes no difference.” Shady
Grove, 559 U. S., at 409 (plurality opinion). To determine
whether a Rule is valid under the Rules Enabling Act, the
only question is whether it “really regulates procedure.”
Sibbach, 312 U. S., at 14. Rule 8 does, so it governs, and
Delaware's affdavit law does not apply in federal court.

200 BERK
v. CHOY
Jackson, J., concurring in judgment
***
The
judgment of the Court of Appeals is reversed, and
the case is remanded for further proceedings consistent with
this opinion.
It is so ordered.
Justice Jackson, concurring in the judgment.
I agree with the Court that Delaware's affdavit require-
ment cannot apply in federal court. I write separately be-
cause, in my view, the relevant conficts are with Federal
Rules of Civil Procedure 3 and 12, not Rule 8.
I
As the majority explains, Delaware's law is, at bottom, an
“affdavit requirement.” Ante, at 190. If a medical mal-
practice plaintiff wants her complaint deemed “fled” and her
case docketed, the statute mandates that an affdavit of merit
signed by a medical professional (or a motion for an exten-
sion of time to fle the affdavit) must accompany the com-
plaint. See Del. Code, Tit. 18, § 6853(a)(1) (2025). By con-
trast, the Federal Rules require no such additional fling.
Rather, “[a] civil action is commenced by fling a complaint
with the court.” Fed. Rule Civ. Proc. 3.
Thus, § 6853 and Rule 3 confict regarding the require-
ments to “commence” a medical malpractice action. If a fed-
eral court were to follow Delaware's law, a plaintiff would
have to do more than merely tender the complaint in order
for his medical malpractice lawsuit to be fled and docketed.
But, under the language of Rule 3, civil suits commence as
soon as the complaint—and only the complaint—has been
fled by the plaintiff. In my view, this clash warrants rever-
sal here.
As the majority explains, our cases make clear beyond
cavil that “a valid [Federal] Rule of Civil Procedure displaces
contrary state law.” Ante, at 192. Thus, the nub of the con-
fict inquiry is to determine whether the State's requirement
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Jackson, J., concurring in judgment
is, in fact, contrary to a Federal Rule. Over time, we have
expressed
this central inquiry in various ways. See, e. g.,
Hanna v. Plumer, 380 U. S. 460, 472 (1965) (asking whether
“the applicable Federal Rule is in direct collision with the
[state] law”); Burlington Northern R. Co. v. Woods, 480 U. S.
1, 4–5 (1987) (asking whether the scope of the Federal Rule
is “ `suffciently broad' ” to “ `control the issue' ” before the
Court, “thereby leaving no room for the operation” of the
state law (quoting Walker v. Armco Steel Corp., 446 U. S.
740, 749–750, and n. 9 (1980))). But as the majority acknowl-
edges, our most up-to-date approach to identifying the neces-
sary confict is to ask whether the Federal Rule and the state
statute “attemp[t] to answer the same question.” Shady
Grove Orthopedic Associates, P. A. v. Allstate Ins. Co., 559
U. S. 393, 399 (2010); see also ante, at 192.
1
Per Shady Grove, once a confict between the State's re-
quirement and a Federal Rule has been identifed, the Fed-
eral Rule displaces the State's requirement so long as the
1
To the extent that the Court suggests that the Federal Rule's plain
text is all that matters when answering this question, that is not what our
precedents hold. In Gasperini v. Center for Humanities, Inc., 518 U. S.
415 (1996), we explained that Federal Rules must be interpreted not solely
based on their text—as the much earlier case of Walker v. Armco Steel
Corp. had suggested in a footnote—but also “with sensitivity to important
state interests and regulatory policies,” 518 U. S., at 427, n. 7. The major-
ity opinion in Shady Grove subsequently criticized Gasperini's “search for
state interests and policies that are `important' ” as “standardless.” 559
U. S., at 405, n. 7. But fve Justices in that case (i. e., a majority) agreed
nevertheless with Gasperini's approach to interpreting the Federal Rules
in this context. See 559 U. S., at 437 (Ginsburg, J., dissenting) (writing
for three other Justices that the Court should “continue to interpret Fed-
eral Rules with awareness of, and sensitivity to, important state regula-
tory policies”); id., at 418 (Stevens, J., concurring in part and concurring
in judgment) (explaining that the Federal Rules “must be interpreted with
some degree of `sensitivity to important state interests and regulatory
policies' ” (quoting Gasperini, 518 U. S., at 427, n. 7)). So, under our prec-
edents, courts must be mindful of state interests and policies when deter-
mining whether a Federal Rule conficts with state law.
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Jackson, J., concurring in judgment
Rule is “valid,” meaning that it “governs only `the manner
and
the means' by which the litigants' rights are `enforced.' ”
559 U. S., at 407 (plurality opinion) (quoting Mississippi Pub-
lishing Corp. v. Murphree, 326 U. S. 438, 446 (1946)); see also
28 U. S. C. § 2072(b) (Rules Enabling Act). And for similar
reasons to those given in Part II–B of the majority opinion,
Rule 3 easily satisfes this standard. See ante, at 198–199;
see also Shady Grove, 559 U. S., at 407 (plurality opinion)
(noting that we have “rejected every statutory challenge to
a Federal Rule that has come before us”).
Accordingly, Delaware's affidavit requirement cannot
apply in federal court.
II
The majority and I start in the same place and ultimately
reach the same conclusion, but we have taken different
paths, marked by different assumptions and nuances. I
agree with the majority that the frst step of today's analysis
is to identify the relevant confict by ascertaining the ques-
tion that the Delaware law and the Federal Rule “attemp[t]
to answer.” Shady Grove, 559 U. S., at 399; see ante, at 192.
But I disagree that, in this case, “the disputed question is
whether Berk's lawsuit may be dismissed because his com-
plaint was not accompanied by an expert affdavit.” Ante,
at 192–193. Here is why.
A
First and foremost, that formulation of the question as-
sumes that Berk's lawsuit has already been properly ac-
cepted by the court clerk (i. e., fled and docketed) and thus
that § 6853 is answering whether the “lawsuit may be dis-
missed” for want of the required affdavit. Ante, at 192.
But that assumption jumps the gun. Delaware's law states
that “[n]o health-care negligence lawsuit shall be fled in this
State unless the complaint is accompanied by: (1) [a]n affda-
vit of merit” or (2) “a motion to extend the time to fle said
affdavit.” § 6853(a)(1) (emphasis added). The statute fur-

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203
Jackson, J., concurring in judgment
ther specifes that “[i]f the required affdavit does not accom-
pany
the complaint or if a motion to extend the time to fle
said affdavit . . . has not been fled with the court, then the
. . . clerk of the court shall refuse to fle the complaint and it
shall not be docketed with the court.” Ibid. (emphasis
added).
Accordingly, the text of § 6853 makes clear that the stat-
ute's frst order of business is not to address the require-
ments for dismissal of an affdavit-free lawsuit such as
Berk's. Instead, § 6853 most directly answers the threshold
question of what is required to start a civil action for medi-
cal malpractice under Delaware law. Delaware's response
is that the plaintiff must submit an affdavit of merit, or
a motion for an extension of time to fle such affdavit,
because (to repeat) the clerk cannot “fle the complaint”
or “docke[t] ” the case w ithout that additi ona l fi l i ng.
§ 6853(a)(1).
Rule 3 provides a completely different answer to the ques-
tion of what is required to start a medical malpractice case.
As explained above, under that Rule, “[a] civil action is com-
menced by fling a complaint with the court”—period. That
answer leaves “no room” for Delaware's insistence that an
affdavit of merit (or a motion for an extension) must be sub-
mitted in order to commence this kind of legal action. Bur-
lington, 480 U. S., at 5. Indeed, Rule 3 uses the uncompro-
mising, declarative phrase “is commenced,” plainly indicating
that Congress meant for the “fling [of] a complaint” to be
both necessary and suffcient to begin any civil case (includ-
ing a malpractice action) in federal court. Cf. Walker, 446
U. S., at 750, n. 10 (“ `Rule 3 simply provides that an action
is commenced by fling the complaint and has as its primary
purpose the measuring of time periods that begin running
from the date of commencement' ” (quoting 4 C. Wright & A.
Miller, Federal Practice and Procedure § 1057, p. 191 (1969)));
Hallstrom v. Tillamook County, 493 U. S. 20, 26 (1989) (read-
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ing Rule 3 to mean that “fling a complaint with the court”
is
synonymous with “fl[ing] suit”).
2
Resisting this conclusion, defendants rely on three cases
to argue that “this Court has long found applicable in federal
court” “state-law condition[s] on allowing suits to proceed.”
Brief for Respondent Beebe 26–27, and n. 11; see also Brief
for Respondent Choy 36–37. But that argument mischarac-
terizes our past rulings. See Cohen v. Benefcial Industrial
Loan Corp., 337 U. S. 541 (1949); Woods v. Interstate Realty
Co., 337 U. S. 535 (1949); Walker v. Armco Steel Corp., 446
U. S. 740.
The majority has already ably explained that defendants
“substantially overread” Cohen for the proposition that “all
state `preconditions to proceeding ' are consistent with the
Federal Rules.” Ante, at 195. I think Walker and Woods
are also easily distinguishable.
2
The majority contends that its dismissal-focused formulation of the
question is the right one because, in this case, “Berk's lawsuit has already
been fled and docketed,” and “we granted certiorari” on the question
“whether Berk's lawsuit may be dismissed.” Ante, at 193, n. 1. That
argument confates the question presented with the “question” that, under
Shady Grove, is supposed to serve as the linchpin of our confict analysis.
559 U. S., at 401. The latter comes not from the facts of the case, but
rather from our interpretations of the potentially conficting state law and
Federal Rule. So, while it may be that the question presented is
“whether Berk's lawsuit may be dismissed,” the relevant question for our
Shady Grove analysis is “what is required to start a medical malpractice
case,” because that is the question that § 6853 and, as it happens, Rule 3,
“attemp[t] to answer,” Id., at 399.
Nor is the majority correct that, regardless, I am “ultimately forced to
grapple with the question whether Berk's lawsuit may be `dismiss[ed].' ”
Ante, at 193, n. 1 (alteration in original). As I stated above, § 6853's con-
fict with Rule 3 is enough to hold that the law cannot apply in federal
court. And, as I have shown, the Rule 3 analysis is about the commence-
ment of the action, not its dismissal. Once we determine that § 6853 and
Rule 3 answer the same commencement-related question, § 6853 cannot
apply in federal court, meaning that Berk's lawsuit cannot be thwarted for
failure to satisfy the requirements of that state law.
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Jackson, J., concurring in judgment
As with Cohen, respondents overstate the effect of
W
alker. There, we held that a federal court sitting in diver-
sity must apply an Oklahoma law that deemed an action
“commenced” upon service of the summons for purposes of
the State's statute of limitations. 446 U. S., at 742. Rule 3,
we explained, “governs the date from which various timing
requirements of the Federal Rules begin to run, but does not
affect state statutes of limitations.” Id., at 751. Here, by
contrast, § 6853 and Rule 3 serve precisely the same function,
in the same context: Both establish when a malpractice law-
suit is deemed initiated (i. e., fled and docketed) for purposes
of determining “the date from which various timing require-
ments of the Federal Rules begin to run.” Ibid. That is
precisely the kind of confict that bars the application of state
law in federal court under our precedents.
3
Defendants' reliance on Woods is similarly unavailing.
There, we held that a federal court sitting in diversity must
apply a Mississippi law prohibiting out-of-state corporations
from bringing suit in the State unless they designated an
agent for service of process. 337 U. S., at 536, n. 1. Missis-
sippi's law was enacted to ensure that only those out-of-state
corporations that consented to being sued in Mississippi had
the privilege of accessing Mississippi's courts. See ibid. In
other words, Mississippi's law had a broad substantive pur-
pose and effect that went well beyond what the Federal
Rules addressed. That was why we had to wade through
“Erie's murky waters” to decide the conficts question that
case presented. See Shady Grove, 559 U. S., at 398; see
3
Proving this point, another provision of the Delaware law, § 6853(a)(4),
provides that a defendant is “not required to take any action with respect
to the complaint . . . until 20 days after plaintiff has fled the affdavit.”
Under the Federal Rules, however, the deadline for a responsive act by
the defendant is anchored to the fling of the complaint. See Fed. Rules
Civ. Proc. 4(m) (a plaintiff must serve the complaint and summons “within
90 days after the complaint is fled”) and 12(a)(1)(A)(i) (a defendant “must
serve an answer . . . within 21 days after being served with the summons
and complaint”).
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also Erie R. Co. v. Tompkins, 304 U. S. 64 (1938). Delaware's
affdav
it requirement, by contrast, is plainly procedural in
scope and well within the territory of the Federal Rules.
In short, our precedents establish that when a state law
and a valid Federal Rule confict—because they answer the
same procedural question—the State's requirement is inap-
plicable in federal court. Because § 6853 answers the same
question about what is required to commence a medical mal-
practice action as the unquestionably valid Rule 3, Dela-
ware's law must give way. See Hanna, 380 U. S., at
469–474.
B
If we accept, for the sake of argument, that the question
Delaware's law attempts to answer is “whether [a medical
malpractice complaint] may be dismissed because [it] was not
accompanied by an expert affdavit,” ante, at 192–193, a
problem arises: The Federal Rule the majority points to does
not answer that same question.
The majority discerns a confict with Rule 8 by reasoning
as follows. With respect to the dismissal-related question
quoted above, Delaware's law says that such a complaint
must be dismissed because the affdavit of merit is missing,
whereas Rule 8 prescribes all “the information a plaintiff
must present about the merits of his claim at the outset of
litigation”—namely, “ `a short and plain statement of the
claim showing that [he] is entitled to relief.' ” Ante, at 193
(quoting Fed. Rule Civ. Proc. 8(a)(2)). “By requiring no
more than a statement of the claim,” the majority continues,
“Rule 8 establishes `implicitly, but with unmistakable clarity,'
. . . that evidence of the claim is not required.” Ante, at 193.
The problem with this reasoning is not that it is based on “a
negative inference” about Rule 8, ante, at 195, n. 2, but rather
the inattentively capacious scope of that negative inference.
I agree that Rule 8(a)'s fnite list “preclude[s] courts” from
imposing additional requirements. Ibid.; see Leatherman v.
Tarrant County Narcotics Intelligence and Coordination
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207
Jackson, J., concurring in judgment
Unit, 507 U. S. 163, 168 (1993). But context is critical: Rule
8
does not purport to establish all that a medical malpractice
plaintiff can be required to say about the merits of his claims
at the beginning of the case, much less that nothing more
than the fling of a complaint can be mandated. Rather, it
(more narrowly) addresses what any “pleading” stating a
claim for relief must contain. See Rule 8(a) (“A pleading
that states a claim for relief must contain . . .” (emphasis
added)). The majority neither holds nor suggests that
§ 6853's affdavit of merit is, itself, a “pleading ”; to the con-
trary, the majority admits that the affdavit is not. Ante, at
194. So, as I see it, Delaware's law—which prescribes what
a plaintiff must submit in addition to his pleadings in order
for his complaint to be fled and his case docketed—does not
actually confict with Rule 8.
The majority acknowledges this “pleading ” problem and
offers, apparently as a solution, yet another formulation of
the question that Rule 8 is answering: Rule 8, it says, tells
us “what information a plaintiff must provide about the mer-
its of his claim.” Ante, at 195. But, again, this description
fails to acknowledge that Rule 8 operates entirely within a
specifc universe: the pleadings. The majority's unbounded
characterization subtly frees Rule 8 from the constraint of
its subject matter, allowing it to expand until it collides with
Delaware's law.
4
4
The majority's description of Rule 8's work is inaccurate even if con-
fned to the universe of pleadings. Rule 8 does not “addres[s] what infor-
mation a plaintiff must provide about the merits of his claim” in the plead-
ings. Ante, at 195 (emphasis added). Instead, with respect to a pleading
that states a claim for relief (as opposed to one that does not, see Rule 7),
Rule 8 governs how much a plaintiff must say concerning his claim. Rule
8's primary purpose is to install a “simplifed pleading system” that re-
quires a complaint to include nothing more than “ `short and plain state-
ment[s]' ” of the claim, the grounds for jurisdiction, and the relief sought.
Swierkiewicz v. Sorema N. A., 534 U. S. 506, 512, 514 (2002). In other
words, Rule 8's innovation is the “short and plain” bit, not the substance
of what is required to be stated in that manner.
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When properly construed, Rule 8 addresses a particular
(
and particularly important) procedural question: “What
must a pleading that states a claim for relief contain?”
5
In
my view, this narrower formulation of the question—the one
tethered to the required contents of a “pleading ”—keeps
Rule 8 within the bounds of its plain meaning, consistent
with Gasperini's command not to overread the Federal
Rules at the expense of “important state interests and regu-
latory policies” in cases such as this one. Gasperini v. Cen-
ter for Humanities, Inc., 518 U. S. 415, 427, n. 7 (1996); see
also n. 1, supra.
Accordingly, because § 6853 does not address or govern the
required contents of a pleading, Delaware's law does not an-
swer the same question as Rule 8. Instead, the State's aff-
davit requirement (which, incidentally, neither describes the
affdavit of merit in relation to a plaintiff 's obligation to state
a claim for relief nor treats it as evidence) is an additional
fling requirement for commencing any medical malpractice
civil action under state law. See § 6853(a)(1) (“No health-
care negligence lawsuit shall be fled in [Delaware] unless
the complaint is accompanied by . . . [a]n affdavit of merit”).
Finding a Rule 8 confict, as the majority does, thus requires
contorting both Rule 8 and § 6853. There is no need to do
so here, especially given the ready confict with Rule 3 (dis-
cussed above) and Rule 12 (described below).
6
5
The answer, under the Rule, is (1) “a short and plain statement of the
grounds for . . . jurisdiction,” (2) “a short and plain statement of the claim
showing that the pleader is entitled to relief,” and (3) “a demand for the
relief sought.” Rule 8(a).
6
To be sure, many Courts of Appeals have also relied on a confict with
Rule 8 to hold that state affdavit-of-merit laws like Delaware's do not
apply in federal court. See Albright v. Christensen, 24 F. 4th 1039, 1048–
1049 (CA6 2022); Gallivan v. United States, 943 F. 3d 291, 293 (CA6 2019);
Pledger v. Lynch, 5 F. 4th 511, 519 (CA4 2021); Young v. United States,
942 F. 3d 349, 351 (CA7 2019). But a closer look at the relevant cases
reveals that these courts, like the majority, got there by manipulating the
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Jackson, J., concurring in judgment
III
The
majority and I appear to agree that Delaware's af-
fdavit requirement—as interpreted by the Delaware Su-
preme Court—conficts with Rule 12(d). See ante, at 193.
That confict suffces to displace § 6853's requirement. But
to the extent that the majority ties its Rule 12 analysis to
the purported Rule 8 confict, see ibid., I think the majority
has gone further than it needs to, introducing incoherence in
the process.
While the statute itself does not so specify, the Delaware
Supreme Court has interpreted § 6853 to mean that (assum-
ing the clerk of court accepts an affdavit-free medical mal-
practice action and dockets the case notwithstanding the
statute's prohibition) “[t]he fling of a healthcare negligence
action without the requisite affdavit of merit constitutes
grounds of dismissal of medical negligence claims as a matter
of law.” Hall v. Sorouri, 996 A. 2d 793 (Del. 2010) (Table).
That reading of Delaware law answers the question, “What
can a court consider when dismissing a medical malpractice
case?” Because “[t]he highest state court is the fnal author-
ity on state law,” Fidelity Union Trust Co. v. Field, 311 U. S.
169, 177 (1940), we must read this statute as that court does,
i. e., as establishing dismissal requirements for medical mal-
practice cases. Thus, if a valid Federal Rule answers that
same dismissal question, § 6853 cannot govern in federal
court. See Shady Grove, 559 U. S., at 398.
relevant question. In Gallivan, for example, the Sixth Circuit posed as
the pertinent question: “[D]oes someone need an affdavit of merit to state
a claim for medical negligence?” 943 F. 3d, at 293. This leading question
not only ignores (as the majority does) that Rule 8 is solely about “plead-
ings,” but, worse, also preordains a confict by naming the very thing that
the state law requires but the Federal Rule does not (i. e., an affdavit).
The Fourth and Seventh Circuits make the same error. See Pledger, 5 F.
4th, at 519 (asking “whether a medical malpractice plaintiff must provide
pre-suit expert support for his claim”); Young, 942 F. 3d, at 351 (asking
whether Rule 8 “require[s] attachments”).
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Enter Rule 12. As the majority correctly explains, Rule
12(
b)(6) provides the “only . . . ground for dismissal based on
the merits,” and Rule 12(d) prohibits courts from considering
“ `matters outside the pleadings' ” in deciding motions to dis-
miss brought under Rule 12(b)(6). Ante, at 193; see also
Stanley v. City of Sanford, 606 U. S. 46, 49 (2025) (explaining
that, under Rule 12(d), a judge considering a motion to dis-
miss must “take as true the well-pleaded facts in the plain-
tiff 's complaint, . . . and [must] not consider evidence beyond
that pleading ”). Furthermore, by all accounts, the affdavit
required by Delaware's law is a “matte[r] outside the plead-
ings.” Rule 12(d); see ante, at 194 (“It is true . . . that an
a f f i d a v i t o f m e r i t i s a d o c u m e n t s e p a r a t e f r o m t h e
`pleading ' ”).
We know the affdavit of merit qualifes as a “matter out-
side the pleadings” for several reasons. For one thing, Dela-
ware law provides that the affdavit is to “accompany” the
complaint. § 6853(a)(1). A thing cannot “accompany” that
of which it is already a part.
7
Indeed, Delaware's Legisla-
ture apparently felt so strongly about the affdavit not being
part of the complaint that it mandated physical separation:
By statute, the affdavit must be fled in its own sealed enve-
lope, alongside (but apart from) the complaint. See ibid.
Nor do the Federal Rules suggest that affdavits of the
nature specifed by the Delaware law can qualify as “plead-
ings.” Rule 7, which sets forth a list of “[p]leadings
[a]llowed” in federal court, does not include an “affdavit” (or
anything like it) on its list.
Pulling these threads together, Delaware's law, as inter-
preted by the Delaware Supreme Court, requires judges to
7
To be sure, plaintiffs can, in limited contexts, “incorporat[e]” certain
documents “into the complaint by reference.” Tellabs, Inc. v. Makor Is-
sues & Rights, Ltd., 551 U. S. 308, 322 (2007). But the affdavit of merit
is not such a document because its content is neither discoverable nor
admissible. See § 6853(d).
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Jackson, J., concurring in judgment
account for a matter outside the pleadings—i. e., the exist-
ence
or suffciency of an affdavit of merit (or lack thereof )—
when deciding whether to dismiss a medical malpractice
case. Rule 12(d), however, forbids such extraneous consid-
erations. And Rule 12 is valid under the Rules Enabling
Act (for similar reasons as the Court lays out in its opinion,
see ante, at 198–199). So Delaware's law cannot be enforced
in federal court.
As far as I can tell, then, there is no daylight between my
view of the Rule 12 confict and the majority's assessment.
But far from “reinforc[ing]” a confict with Rule 8, ante,
at 193, our shared evaluation of Rule 12 is, to me, yet another
reason why Delaware's law is not in confict with Rule 8.
See Part II–B, supra. The conficts analysis concerning
these two Rules is based on diametrically opposed charac-
terizations of Delaware's affdavit of merit: The affda-
vit must be either a “matter outside the pleadings” (and
thus § 6853 conficts with Rule 12, per the Delaware Su-
preme Court's decision in Hall) or it is part of what the
pleadings must contain (giving rise to the purported confict
with Rule 8). A coherent conficts analysis cannot have it
both ways.
* * *
Read for what they are—by their “plain meaning,” sensi-
tive to context yet without distortions created by the task
of checking for a confict, see Walker, 446 U. S., at 750, n. 9;
Gasperini, 518 U. S., at 427, n. 7—Rules 3 and 12 answer the
same questions as Delaware's affdavit requirement. That
means that the majority and I share the same conclusion:
There is a confict between state law and valid Federal
Rules, precluding application of Delaware's affdavit require-
ment in federal court. For the reasons discussed above, I
think the majority is wrong to further maintain that § 6853
answers the same question as Rule 8. And I cannot see how
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212 BERK
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outside the pleadings” (for Rule 12-confict purposes) and
a
lso part of the “pleadings” (for Rule 8-confict purposes).
Therefore, I concur only in the judgment.
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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. 188, line 7: The sentence “This Court has consistently rejected efforts
by lower federal courts to require more information than Rule 8 re-
quires.” is replaced with “Lower federal courts have sometimes tried to
demand more information than Rule 8 requires for certain kinds of
claims. This Court has consistently rejected such efforts.”
p. 200, Part I, line 3: “his” is changed to “hers”
p. 204, line 4: “from 1949, arguing ” is changed to “to argue”
p. 206, line 1: “also” is inserted before “Erie R. Co.”