USA v. Peterson

UNITED STATES DISTRICT COURT
DISTRICT OF MINNESOTA
UNITED STATES OF AMERICA,
Plaintiff,
v.
ERIC SCOTT PETERSON,
Defendant.
Case No. 25-cr-0004 (LMP/LIB)
ORDER DENYING DEFENDANT’S
FIFTH MOTION IN LIMINE
Garrett S. Fields and David M. Classen, United States Attorney’s Office, Minneapolis,
MN, for Plaintiff.
Jean M. Brandl, Office of the Federal Defender, Minneapolis, MN, for Defendant.
Federal Rule of Criminal Procedure 16(a)(1)(G)(ii) provides that the Court must set
a deadline for the United States to make expert disclosures to the Defendant, which “must
be sufficiently before trial to provide a fair opportunity for the defendant to meet the
government’s evidence.” 	Here, that deadline was 28 days before trial: March 13, 2026.
ECF No. 23 at 2. 	Defendant Eric Scott Peterson now moves for an order excluding any
expert witness by the United States because the United States did not provide its formal
Rule 16 disclosures until March 24, 2026: 17 days before trial. ECF No. 83. The United
States concedes that it did not timely provide formal Rule 16 disclosures but argues that
wholesale exclusion of its expert witnesses is unwarranted. ECF No. 84.
When the United States fails to comply with the Rule 16 expert disclosure
requirement, courts have “broad discretion” to fashion appropriate relief. United States v.
Ortega, 150 F.3d 937, 943 (8th Cir. 1998). 	Even when there is a violation of Rule 16,
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exclusion of expert witness testimony is not necessarily required. See United States v. Bull,
8 F.4th 762, 768 n.6 (8th Cir. 2021). Rather, the remedy must be “the least severe sanction
which will adequately punish the government and secure future compliance.” 	United
States v. DeCoteau, 186 F.3d 1008, 1010 (8th Cir. 1999) (citation omitted). In determining
a suitable sanction, the Court “must weigh the reasons for the government’s delay and
whether it acted intentionally or in bad faith; the degree of prejudice, if any, suffered by
the defendant; and whether any less severe sanction will remedy the prejudice and the
wrongdoing of the government.” Id. (citation omitted).
The 	Court 	declines 	to 	exclude 	the 	United 	States’ expert 	witnesses 	because
Peterson’s one-page motion does not attempt to show how he was prejudiced by the United
States’ 11-day delay. ECF No. 83. Nor likely could he. As the United States explains, it
provided Peterson with its expert reports months before the trial deadline, and three days
before the Rule 16 deadline, the United States provided Peterson with “preliminary notice
of the possible expert testimony” from four expert witnesses. ECF No. 84 at 3. The United
States also provided short summaries of the expert witnesses’ anticipated testimony in its
trial brief filed two days before the Rule 16 deadline. 	ECF No. 56 at 10–11. 	Given that
Peterson was “provided notice that [the experts] would be testifying” and was “made aware
of the nature of [the experts’] testimony,” Peterson has “failed to show any prejudice” from
the United States’ 11-day delay in providing formal Rule 16 notices. 	United States v.
Shepard, 462 F.3d 847, 866 (8th Cir. 2006).
Moreover, the United States provided its formal Rule 16 disclosures 17 days before
trial, a time period that the Eighth Circuit has considered sufficient to provide “a fair
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opportunity for the defendant to meet the government’s evidence.” 	Fed. R. Crim.
P. 16(a)(1)(G)(ii); see Shepard, 462 F.3d at 866 (affirming introduction of expert testimony
when witness was disclosed one week prior to trial and formal Rule 16 notice was never
provided); Ortega, 150 F.3d at 944 (affirming introduction of expert testimony when
substance of witness’s testimony was disclosed one week prior to trial)
Finally, considering the “reasons for the government’s delay,” DeCoteau, 186 F.3d
at 1010, the United States explains that it was waiting for a signed expert disclosure from
Forensic Scientist (FS) Ashley Mack, the toxicologist who conducted the retrograde
extrapolation on the alcohol concentration of Peterson’s blood sample. ECF No. 84 at 4.
Evidently, Peterson had asked FS Mack to perform additional calculations in advance of
trial, and FS Mack wanted to finalize those calculations before submitting a signed
summary of expected testimony. Id. The delay in submitting FS Mack’s formal Rule 16
notice appears, then, partially attributable to Peterson, which further weakens Peterson’s
request to exclude the United States’ expert witnesses.
Accordingly, in the absence of any prejudice to Peterson, the Court declines to
impose “the most severe discovery sanction available—wholesale exclusion of evidence.”
Johnson, 228 F.3d at 926. 	And because Peterson does not request or propose any less
severe sanction, the Court denies his fifth motion in limine in its entirety.1
1 	This conclusion also recognizes and credits the parties’ representations at the
March 25, 2026 pretrial conference that they were still negotiating various witness and
evidentiary issues. While the Court had reviewed the United States’ proposed witness list,
ECF No. 70, and trial brief, ECF No. 56, which listed and discussed the United States’
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ORDER
Based upon the foregoing, and all the files, records, and proceedings herein, IT IS
HEREBY ORDERED that Peterson’s Fifth Motion in Limine (ECF No. 83) is DENIED.
Dated: April 6, 2026 	s/Laura M. Provinzino
Laura M. Provinzino
United States District Judge
expert witnesses, Peterson did not raise any challenges to the sufficiency of the United
States’ disclosures or any other concerns about the United States’ expert witnesses.
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