In what amounted to a 6-3 decision, issued without explanation, the court turned down California's request for more time. Conservative justices Samuel Alito, Clarence Thomas and Antonin Scalia broke from the majority decision, with Thomas and Scalia joining in a formal written dissent.
"California must now release upon the public nearly 10,000 inmates convicted of serious crimes, about 1,000 for every city larger than Santa Ana," Scalia wrote, adding that the court's order is a "terrible injunction."
Working with the Berkeley-based Prison Law Office, attorney Paul Clement and the other prisoners' attorneys call California's request for more time "truly extraordinary" and denounce what they call "open defiance of the federal judiciary."
The prisoner-release order stems from a 2011 Supreme Court decision that upheld a three-judge panel's determination that the prison system population needed to be reduced to 137.5 percent of design capacity.
PHOTO: Several hundred inmates crowd the gymnasium on May 20, 2009, at San Quentin State Prison. Associated Press/ Eric Risberg