San Jose, Calif. ? The U.S. Supreme Court on Monday scrapped a 30-year-old California sentencing law, opening the door for thousands of inmates to argue for modest breaks on their prison terms and forcing criminal justice systems across the state to cope with the fallout.

In a 6-3 ruling, the Supreme Court struck down a key element of the state’s sentencing scheme by concluding that judges cannot increase prison terms based on evidence that was never considered by a jury. While the ruling is unlikely to benefit a significant segment of California’s bulging prison population, legal experts say it should influence state leaders as they press forward with plans to overhaul the state’s sentencing system.

The Supreme Court’s decision came as little surprise. The justices struck down key elements of the federal sentencing system two years ago based on the same concerns, and expressed doubt over California’s law during arguments before the court last fall.

For prosecutors and defense lawyers in counties such as Santa Clara, it could take months to evaluate the complex ruling and its consequences for inmates doing time. Michael Kresser, director of a San Jose-based appellate project that handles the bulk of criminal appeals from the South Bay, estimates he has about 200 cases from Santa Clara and nearby counties in which defendants may be able to argue for a sentencing break.

The Supreme Court ruling does not impact California’s three-strikes-and-you’re-out law or most serious criminals facing potential life terms for murder, rape and other violent felonies. More likely it will affect the typical felony case against burglars, robbers and defendants who commit sexual assault who do not face those stiff punishments.

But the ruling does promise to force defense lawyers, prosecutors and judges to grapple with new sentencing hearings across California.

“How many sentences are going to be reduced is open to question,” Kresser said. “But for now the question is how do we get these people back before some court somewhere to vindicate their rights.”

Assistant District Attorney David Tomkins said prosecutors have not assessed the local impact of the decision, but “understand the significance.”

Attorney General Jerry Brown said he expects prosecutors to fight to preserve higher sentences against inmates still serving their time by presenting the same evidence to juries that was previously found by judges.