Arizona v. Youngblood

A ten-year-old boy was kidnapped from a church carnival and assaulted for one and a half hours. When the boy finally got home, his mother took him to the hospital where the doctor collected evidence using a sexual-assault kit the police department supplied to the hospital. In addition to the blood samples, hair samples, saliva samples, and swabs and smears the doctor took, the boy’s underwear and T-shirt were given over to the police. The police examined the sexual-assault kit to determine that sexual contact had occurred but did not perform any tests to help identify the assailant. Nine days after the incident, the boy identified Youngblood (defendant) in a photographic lineup shown to him by police. Youngblood was arrested about four weeks later. About two years later, the police examined the boy’s clothing for the first time and found two semen stains. The police tried to identify the assailant by testing the semen stains but were unable to do so. The clothing had not been refrigerated during the intervening two years. The police had followed standard department procedures regarding the preservation and testing of evidence. At trial, Youngblood called an expert witness who testified to what could have been shown if further tests had been conducted on the samples or the clothing had been refrigerated. Nonetheless, the jury found Youngblood guilty. The court of appeals reversed the conviction, holding that the destruction of evidence that could have exonerated the defendant was a violation of due process. The United States Supreme Court granted certiorari.