The Texas Court of Criminal Appeals wants more time to determine whether Jose Garcia Briseno was mentally retarded when he killed Dimmit County Sheriff Ben Murray in a 1991 home burglary.
The judges acted after Briseno's appeals attorneys raised new questions about his mental capacity based on the recent U.S. Supreme Court decision that banned the execution of the mentally retarded.
Michelle Lyons, a prison spokeswoman, said Briseno was on death row at Livingston, Texas, meeting with his family when he learned the news at about 2 p.m. He had not been transported to the Walls Prison in Huntsville where the executions are performed.
Briseno would have been the 19th convicted killer executed this year in Texas. Several executions have been delayed recently because of questions about mental retardation.
A total of 274 convicted killers have been executed in Texas since the state restored the death penalty in 1982, more than any other state in the nation.