A federal appeals court blasted Texas courts for refusing to hold a hearing to consider evidence that a convicted killer may be mentally disabled, therefore ineligible for the death penalty.

A three-judge panel of the 5th U.S. Circuit Court of Appeals in New Orleans ordered a federal evidentiary hearing for Michael Wayne Hall, who was sentenced to die for the 1998 slaying of a 19-year-old woman abducted as she rode her bicycle to work.

The panel criticized both the trial court and the state's highest criminal appeals court for relying on written arguments rather than holding an open evidentiary hearing in Hall's case.

"The facts before us are a core manifestation of a case where the state failed to provide a full and fair hearing and where such a hearing would bring out facts which, if proven true, support ... relief," the judges said.

The ruling late Monday reversed the findings of a federal district judge who upheld the state courts' rejection of defense attorneys' claims that Hall is mentally disabled. The U.S. Supreme Court has ruled that mentally disabled people may not be executed.