A Georgia death row inmate convicted of killing a fellow inmate is set to be executed later this month.

The Commissioner of the Department of Corrections on Wednesday set the execution of Warren Lee Hill for July 15 at 7:00 p.m. Earlier Wednesday a judge had signed a warrant setting a window for the execution between noon on July 13 and noon on July 20.

Hill's lawyers have repeatedly said he's mentally disabled and therefore should not be executed. The execution of mentally disabled offenders is prohibited by state law and a 2002 U.S. Supreme Court decision.

The state has said Hill's defense lawyers have failed to prove his mental disability beyond a reasonable doubt.

Hill has come within hours of being executed on two previous dates.

Tags: death penalty, Warren Lee Hill, execution date