McDaniel v. Brown

Troy Brown (defendant) was convicted of sexual assault of a 9-year-old child in a Nevada state trial court. The child was assaulted in the dark and could not identify her assailant but said that the assailant reminded her of Troy Brown or his brother Trent, who also lived in the same trailer park as Troy and the victim. Semen taken from the child’s underwear and the rape kit had a DNA profile that matched Troy Brown’s DNA. The government’s expert, Renee Romero, testified that the probability of a person from the general populace sharing the same DNA was 1 in 3,000,000. Romero had an expert who prepared a report that Romero did not present at trial but relied upon in appeals. That report, termed the Mueller Report, argued that Romero’s testimony engaged in the prosecutor’s fallacy, in which the possibility of a random match was mistaken for the possibility of someone else committing the crime. The possibility of another perpetrator committing the crime was particularly significant in comparing Troy Brown’s DNA with one or more of his brothers’ DNA, which had a much higher probability of similarity. Romero had testified that such a likelihood was 1 in 6,500, but in fact, the likelihood was even lower, perhaps as low as 1 in 66. After Brown’s conviction, Brown filed a petition for a writ of habeas corpus against E. K. McDaniel (plaintiff), the warden of the prison where Brown was incarcerated for that crime. The trial court set aside DNA testimony used against Brown and granted him relief on the grounds that without the DNA evidence, a reasonable doubt that Brown committed the crime would exist for a rational jury. The Ninth Circuit affirmed that ruling, and the government appealed.