United States v. Ausby

United States Court of Appeals for the District of Columbia Circuit · 2019 · Evidence

916 F.3d 1089 (D.C. Cir. 2019)

Updated August 22, 2026

EvidenceNapuefalse testimonymaterialityreasonable likelihood28 U.S.C. § 2255due processmicroscopic hair comparison

Facts

At Ausby's murder and rape trial, the government presented several forms of evidence linking him to the victim's apartment and death, including eyewitness sightings, a thumbprint in the apartment, scented oil tied to Ausby, and ballistics evidence that only potentially matched his handgun. The government also presented FBI Agent Robert Neill, who testified that hairs found in the victim's apartment and on her body were "microscopically identical" to Ausby's hairs and suggested they either came from Ausby or from someone with microscopically identical hair. In closing and rebuttal, the prosecution emphasized this testimony, even asserting that although hair comparison was not generally a positive means of identification, "it amounts to a positive means here." Decades later, the government conceded that this hair-comparison testimony was false and misleading and that the government knew or should have known that at the time of trial.

Issue

Whether the government's knowing use of Agent Neill's false and misleading microscopic hair-comparison testimony was material under Napue so as to require vacatur of Ausby's conviction under 28 U.S.C. § 2255. More specifically, the question was whether there was a reasonable likelihood that the false testimony could have affected the jury's judgment.

Rule

A Napue violation occurs when the government introduces false or misleading testimony, or allows it to go uncorrected, even though the government knew or should have known it was false. Relief is not automatic: the defendant bears the burden of showing materiality, meaning the false testimony could in any reasonable likelihood have affected the judgment of the jury, i.e., could have altered the outcome of the case and undermined confidence in the verdict. The court declined to replace the "reasonable likelihood" formulation with "reasonable possibility" and declined to treat the standard as shifting the burden to the government under Chapman harmless-error review.

See the holding & full analysis

Create a free KwikCourt account to unlock the rest of this brief — and practice the case.

The court's holding and reasoning
Doctrine tests, pitfalls & exam hypotheticals
10 practice questions + 4 AI-graded essays on this case

Free sample · practice this case

Test yourself

One of 10 multiple-choice questions for this case. Pick an answer to see why.

In a homicide trial in Detroit, the prosecution's theory is that Leo Martin entered a warehouse the night of the killing. Leo admits he had been in the warehouse two days earlier for legitimate business, and most of the government's evidence—his fingerprint on a door, surveillance showing him near the block earlier that week, and a possible but inconclusive firearm match—fits that explanation. The government also presents a forensic analyst who falsely testifies, with the prosecutor's knowing use, that fibers found on the victim's jacket were microscopically identical to fibers from Leo's coat, and the prosecutor argues in rebuttal that this evidence effectively places Leo at the killing itself.

Assuming falsity and government knowledge are established, is the false fiber testimony material under the governing standard?

Explanation. Materiality under Napue asks whether the false testimony could in any reasonable likelihood have affected the judgment of the jury. The defendant need not show he more likely than not would have been acquitted, and the burden does not shift to the government under Chapman. Where the false evidence is the primary proof that directly undermines the defense theory, it is material even if other evidence is substantial.