SAN FRANCISCO (CBS / AP) — California prison officials say they won’t appeal to the state Supreme Court a ruling invalidating the state’s three-drug cocktail means of execution.

Instead, a California Department of Corrections and Rehabilitation spokeswoman said the state would continue developing an execution protocol that uses a single drug. Several other states have turned to the single-drug execution in recent years in response to legal challenges.

A CDCR spokeswoman said Gov. Jerry Brown ordered prison officials to continue working on the single drug method rather than fighting to keep the three-drug cocktail in place.

Executions will remain on hold until the state officially adopts the procedure and federal courts sign off on the new method, which could take years. There are 725 inmates on California’s death row.

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