In an 8-1 ruling, the justices said this judge-driven system violates a defendant's right to a jury trial.
The ruling will likely give new sentencing hearings to inmates who were recently sentenced to death in Florida, but the justices in the past have said such new rulings do not apply automatically to old cases.
Tuesday's ruling relied on a 2002 decision that struck down Arizona's judge-driven system for deciding death penalty cases. Despite that ruling in the case of Ring vs. Arizona, the Florida courts had continued to uphold death sentences there on the grounds that juries had recommended death as the proper verdict.
But on Tuesday, the justices decided Florida must move to a sentencing system that gives juries the final word. The ruling will mean a new sentencing hearing for Timothy Hurst, who was convicted of stabbing and killing a a co-worker at a Popeye's restaurant in 1998.
He was tried twice, and the jury, though divided, recommended a death sentence, and the judge imposed one.
"The 6th Amendment protects a defendant's right to an impartial jury," she said. "This right required Florida to base Timothy Hurst's death sentence on a jury verdict, not a judge's fact-finding. Florida's death sentencing scheme, which required the judge alone to find the existence of an aggravating circumstance, is therefore unconstitutional."
Dissenting alone, Justice
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