This educational guide is based on the linked primary sources. It is not a Court publication, is not affiliated with the Court, and is not legal advice.
In brief
Overview
Marvin Peugh challenges the application of the 2009 federal sentencing guidelines, which are harsher than the 1998 guidelines that were in effect when his crime was committed. The issue is whether applying the newer, harsher guidelines retroactively violates the Constitution’s Ex Post Facto Clause.
Background and question before the Court
According to Stephen B. Kinnaird, the central legal question is whether the retroactive application of the 2009 sentencing guidelines to Marvin Peugh’s case violates the Ex Post Facto Clause.
What each side argues
Petitioner (Marvin Peugh)
According to Stephen B. Kinnaird, retroactive application of the 2009 guidelines, which are harsher than the 1998 guidelines, violates the Ex Post Facto Clause because it creates a significant risk of increased punishment.
Petitioner argues that the district court gave undue deference to the sentencing guidelines as a legal matter.
Petitioner contends that the former (1998) guidelines range would have resulted in a more appropriate sentence than the 2009 range.
United States (Respondent)
According to Eric J. Feigin (Respondent), according to Eric J. Feigin (Respondent), the guidelines do not impose a substantive legal constraint on a district court’s sentencing discretion; judges may impose sentences unrelated to any guidelines range.
According to Eric J. Feigin (Government), according to Eric J. Feigin (Government), after Supreme Court decisions in Gall, Kimbrough, Irizarry, Nelson, and Spears, the argument that guidelines impose a substantive legal constraint on sentencing discretion no longer exists.
What happened at oral argument
Justice Scalia asked whether the sentencing schedule is mandatory.
Justice Sotomayor asked, “Is that what your definition of legal consequence is?”
Justice Scalia asked whether requiring consideration of victim or relative testimony, a change in sentencing law, is permissible.
According to Justice Sotomayor, justice Sotomayor sought clarification on the rule governing whether changes like victim testimony constitute an Ex Post Facto violation.
Justice Scalia asked whether the statute in question permits a ten‑day period.
According to Justice Scalia, justice Scalia questioned whether blindly applying the guidelines without considering the factors in 18 U.S.C. § 3553 constitutes reversible error.
Justice Kagan asked whether judges should be allowed to give deference to the guidelines.
Chief Justice Roberts asked how a court should answer the question of guideline deference.
- [1] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 3
- [2] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 6
- [3] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 20
- [4] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 22
- [5] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 39
- [6] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, pp. 44–45
- [7] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, pp. 44–45
- [8] 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdf, p. 54
What the Court decided
Why it matters
Sentencing guidelines carry a presumption of reasonableness at the appellate level, affecting how lower courts’ sentencing decisions are reviewed.
Terms to know
No glossary terms are available for this guide.
Primary sources
Read the source materials on the official site or open the immutable repository copy used for this guide.
- 4aa16688977c81a65881-r1-9777734eaa3c7da0.pdforal argument transcript
Guide generated September 24, 2026. Automated validation accepted this version.