JACKSON (AP) — Attorneys for condemned inmate Earl Wesley Berry have asked a federal appeals court to stop Berry’s scheduled May 21 execution.

Berry has also asked Gov. Haley Barbour for clemency, which the governor would not be expected to grant. Last year, just before Berry’s execution was stopped, Barbour refused a clemency request.

Berry’s attorney, Jim Craig of Jackson, asked the 5th Circuit Court of Appeals to stop the execution on grounds Berry is mentally retarded and cannot be executed.

The 5th Circuit had not taken any action early Friday. The state was expected to file a response Friday to Berry’s motion.

Thursday’s filing in the 5th Circuit came hours after the Mississippi Supreme Court declined to hear any more appeals from Berry, rejecting a request to review Berry’s mental retardation arguments and claims against the state’s lethal injection method.

Berry has been sentenced to death for the 1987 beating death of Mary Bounds. He confessed to abducting Bounds, 56, as she left church choir practice, killing her and dumping her body on a rural road in north Mississippi.

“No one who has ever spent any amount of time with (Berry) doubts that he is mentally retarded,” Craig wrote in court papers.

Berry’s attorneys contend Mississippi uses a lower dosage of drugs and lesser-trained personnel than Kentucky. Attorney General Jim Hood has described Mississippi’s procedures as “substantially similar” to Kentucky’s.

The 5th Circuit had rejected Berry’s previous request for a stay. If it does so again, his attorneys are expected to appeal to the U.S. Supreme Court. That court stopped Berry’s October execution while it considered the Kentucky case.

A 2002 ruling from the same court exempt mentally disabled prisoners from being executed.