## Facts

- A nine-year-old girl was raped in her bedroom in a Nevada trailer park around 1:00 a.m. on January 29, 1994.
- Troy Brown lived in the same trailer park with his brothers and knew the victim’s family.
- The victim’s mother had been at a bar with Brown earlier that night; Brown was heavily intoxicated and returned home later than expected for the short walk.
- Witnesses described a man in dark clothing and a cowboy hat stumbling between Brown’s trailer and the victim’s trailer near the time of the assault.
- At trial, the State introduced DNA evidence from semen recovered from the victim’s underwear; the State’s expert testified the DNA matched Brown and gave a statistic described as a 1 in 3,000,000 probability of another person matching in the general population.
- Brown was convicted in Nevada state court of sexual assault and related offenses and sentenced to life with the possibility of parole after 10 years; the Nevada Supreme Court affirmed the sexual-assault convictions and later denied post-conviction relief.
- In federal habeas proceedings under 28 U.S.C. § 2254, the district court allowed a post-trial expert report criticizing the State’s DNA statistics as reflecting the “prosecutor’s fallacy” and suggesting a much higher match probability among brothers.
- Relying heavily on that post-trial critique, the district court discounted the trial DNA evidence and granted habeas relief for insufficient evidence under Jackson v. Virginia; the Ninth Circuit affirmed.

## Issues

1. Whether a federal habeas court misapplies Jackson v. Virginia by discounting evidence admitted at trial based on post-trial expert analysis when assessing evidentiary sufficiency under § 2254.
2. Whether an asserted due process challenge to allegedly misleading DNA-statistical testimony was properly before the Court when the case had been litigated below as a Jackson sufficiency claim.

## Decision

- The Supreme Court vacated the Ninth Circuit’s judgment and remanded.
- The Court held the lower federal courts clearly misapplied Jackson by effectively removing the trial DNA evidence from the sufficiency analysis based on post-trial expert critique.
- The Court declined to decide any freestanding due process challenge to the DNA testimony because it had not been properly raised and adjudicated in the courts below, leaving that question for consideration on remand to the extent properly preserved.

## Legal Principles

- Under Jackson v. Virginia, evidentiary sufficiency is assessed by asking whether, on the evidence admitted at trial, any rational trier of fact could have found guilt beyond a reasonable doubt.
- In § 2254 habeas review, the sufficiency inquiry must be confined to the trial record; a federal court may not use post-trial evidence to “correct,” exclude, or discount evidence the jury heard.
- Even if trial evidence is arguably flawed or erroneously admitted, it remains part of the record for Jackson sufficiency analysis; admissibility and scientific perfection are not the Jackson question.
- Post-trial expert materials may be relevant to other constitutional theories (e.g., due process or ineffective assistance), but they cannot be used to reweigh the trial proof under Jackson.
- A new constitutional theory not litigated and resolved below generally will not be decided in the first instance by the Supreme Court.

## Conclusion

The Court held that federal habeas courts evaluating a Jackson sufficiency claim must consider the entire body of evidence admitted at trial and may not negate that evidence through post-trial expert critique; it therefore vacated the Ninth Circuit’s grant of relief and remanded for further proceedings, including any properly preserved due process arguments about the DNA testimony.


McDaniel v. Brown, 558 U.S. 120 (2010)