California has the most death row inmates of any state. Click here for an interactive map. Data from DeathPenaltyInfo.org

The execution, which would have been California's first in five years, was scheduled for Thursday, after being delayed slightly on Monday. Brown was convicted of murdering and raping a 15-year-old girl in 1980.

U.S. District Judge Jeremy Fogel refused to block the execution last Friday, but the appeals court requested late Monday that Fogel examine whether California’s new execution laws comply with U.S. Supreme Court guidelines and the U.S. 9th Circuit Court of Appeals ordered a federal judge to review the legality of a lethal injection execution.

The appeals court said that Fogel was wrong in asking Brown to choose between fatal doses of the anesthetic drug sodium thiopental or taking a three-drug cocktail. According to the appeals court, the option was “not consistent with California state law.” An inmate can choose to die either through lethal injection or the gas chamber. The court has also questioned the constitutionality of the protocol of using a three-drug cocktail. 

Fogel denied a stay for Brown’s execution last week by citing a 2008 Supreme Court decision that deemed the three-drug system constitutional.

Brown had previously sent appeals to federal and state courts arguing that California’s death penalty regulations were improperly adopted and that he could be subjected to a painful death. 

His appeal to block the execution was denied by Marin County Superior Court Judge Verna Adams on Monday. Adams said Brown could not prove he would suffer from pain under the current regulations. But Governor Schwarzenegger delayed the execution set for Wednesday to give him time to consider clemency. 

Brown is one of 700 prisoners on Death Row waiting at San Quentin prison in Marin County. It is unlikely that any other executions will occur until next year, and Attorney General Jerry Brown has suspended all executions set for after Sept. 30 because of a drug shortage. 

The state currently has a 7.5 gram supply of sodium thiopental set to expire on Friday. It is the first drug used in the three-drug mix, used to induce unconsciousness. 

Hospira, the manufacturer of the drug, said new supplies will not be available until next year. Hospira cited “raw-material supplier issues” as a problem. 

Currently running for governor of California, Jerry Brown defended his stance against the death penalty in a debate with Republican candidate Meg Whitman Tuesday night. Whitman has accused Brown of flip-flopping on the issue.

The last execution set in California was for Michael Morales in 2006. It was put on hold by Fogel who ruled the potential for inhumane death. A Sept. 14 hearing date to discuss an execution date for Morales was cancelled. 

Reach reporter Jenny Chen here.

Reach editor Olga Khazan here.

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