The Texas Board of Pardons and Parole’s six members voted unanimously to deny the request. The decision came as lawmakers raised concerns that the courts were not properly implementing a groundbreaking 2013 “junk science” law that was intended to provide justice to people convicted based on scientific evidence that has since changed or been debunked.

A Texas man who could be the first person in the U.S. executed for a murder conviction tied to the diagnosis of shaken baby syndrome is facing a lethal injection.

The action by the Texas Court of Criminal Appeals comes one day before Texas inmate Robert Roberson is scheduled for execution.