The Texas Supreme Court has temporarily halted the planned execution of Robert Roberson, granting him a stunning 11th-hour reprieve on Thursday — the same day he was set to receive a lethal injection at a state penitentiary in Huntsville. The stay of execution came just hours after a bipartisan group of Texas lawmakers voted to subpoena Roberson to appear before a Texas House committee. Their unprecedented move prompted Texas Supreme Court justices to delay Roberson’s execution while a lower court resolves a separation-of-powers conflict raised by the subpoena.

Roberson’s reprieve came as prison officials in Alabama killed 36-year-old death row prisoner Derrick Dearman, forcing a lethal cocktail of three drugs into his veins. He was the 20th prisoner to have been executed this year across eight U.S. states. Ahead of the execution, Dearman’s lawyers argued his trial counsel failed to present the jury with information about his lifelong and severe mental illness.