The ruling, which was not along the high court's ideological lines, came in the case of Sandy Williams, who was convicted of rape in Illinois. Williams opted to be tried by a judge, not a jury.
At his trial, Sandra Lambatos, a forensic specialist at the Illinois State Police lab, testified she matched a DNA profile produced by an outside laboratory, Cellmark, to a profile the state lab produced using a sample of Williams' blood.
She told the judge Cellmark was an accredited laboratory and that business records showed that vaginal swabs taken from the victim, L. J., were sent to Cellmark and returned. She offered no other testimony -- leaving that for other witnesses -- and did not vouch for the accuracy of Cellmark's profile.
Defense attorneys tried to get her testimony excluded based on the constitutional right to confront evidence.
Illinois courts affirmed the judge's ruling to include the evidence, saying Lambatos' evidence was not used to prove guilt, and the U.S. Supreme Court agreed in an opinion written by Justice Samuel Alito. Liberal Justice Stephen Breyer joined the majority. Justice Clarence Thomas joined the judgment, though he disagreed with the reasoning used to get there.
"Under our Confrontation Clause precedents, this is an open-and-shut case," Kagan said. "The state of Illinois prosecuted Sandy Williams for rape based in part on a DNA profile created in Cellmark's laboratory. Yet the state did not give Williams a chance to question the analyst who produced that evidence."