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Supreme Court decisions
No. 25-580Jun 1, 2026Crime and Law EnforcementVacated and remanded

The question

Whether a court assessing harmless error on federal habeas review may consider post-trial evidence that the jury never saw when deciding whether a witness's testimony was material to the jury's verdict.

Whitton v. Dixon

What the Court decided

The Court vacated the Eleventh Circuit's judgment denying habeas relief and remanded. The Court of Appeals should not have considered post-trial DNA evidence when assessing whether the Florida Supreme Court reasonably determined that the informant's testimony was immaterial to the jury's verdict. Because that DNA evidence did not exist at trial and was never presented to the jury, it could not have influenced the verdict and therefore sheds no light on whether the testimony did. The Court expressed no view on whether the state court's determination was reasonable in light of the trial evidence, leaving that for the Court of Appeals to assess on remand.

How the justices split

Unanimous
In favor 9
Roberts
Thomas
Alito
Sotomayor
Kagan
Gorsuch
Kavanaugh
Barrett
Jackson

Per curiam (unsigned)

Delivered by the Court

The Court held that the Court of Appeals erred by considering post-trial DNA evidence when evaluating whether the Florida Supreme Court reasonably determined that the informant's testimony was immaterial to the jury's verdict. Under Brecht, the question is whether the constitutional error had a substantial and injurious effect on the jury's verdict, and evidence that did not exist at trial and was never presented to the jury could not have influenced that verdict. The Court expressed no view on whether the state court's determination was reasonable in light of the trial evidence, or on the State's exhaustion argument, leaving both for the Court of Appeals on remand.

How we know · 5 sourced claims
  • The decision was issued per curiam with no noted dissents or concurrences.

    Source: syllabus, lineup

  • The Court vacated the Eleventh Circuit's judgment denying Whitton's application for habeas relief.

    Source: syllabus, Held

  • The Court of Appeals considered post-trial DNA evidence that was never presented to the jury and did not exist at the time of trial when analyzing the state court's determination.

    Source: syllabus, Held

  • The Court reasoned that because the post-trial DNA evidence could not have influenced the jury's verdict, it sheds no light on whether the informant's testimony influenced that verdict under Brecht v. Abrahamson.

    Source: syllabus, Held

  • The Court expressed no view on whether the Florida Supreme Court's determination was reasonable in light of the trial evidence, leaving that for the Court of Appeals to assess on remand.

    Source: syllabus, Held

Read the opinion on supremecourt.gov