( CNN ) -- A court in Fulton County , Georgia , has temporarily stopped the scheduled Monday night execution of condemned murderer Warren Hill . Hill was sentenced to death for the 1990 killing of Joseph Handspike , another inmate in a Georgia state prison . He was convicted of beating Handspike to death with a nail-studded board while serving a life sentence in the 1985 killing of his girlfriend , Myra Wright . His lawyers have argued that Hill is mentally retarded . Last minute stay of execution granted in February . `` Today , the Court found that more time is needed to explore Mr. Hill 's complaint , which raises serious concerns about the extreme secrecy surrounding the execution process in Georgia , and the new Lethal Injection Secrecy Act , which took effect one day before Georgia issued a death warrant for Mr. Hill , '' Brian Kammer , Hill 's attorney said in a statement . Monday is not the first time Hill 's execution has been halted . He had previously been scheduled to die last July , but the state Supreme Court stopped the execution on procedural grounds . Hill was granted another stay in February . According to Kammer , a briefing on Hill 's complaint will take place Thursday . A new execution date is expected to be set for the same day , he said . `` Ultimately , we are hopeful that the United States Supreme Court will hear Mr. Hill 's pending Petition for Writ of Habeas Corpus , and will have the opportunity to consider the important new evidence in this case , that there is unanimous consensus among all the doctors who have examined Mr. Hill , including three who previously testified for the state , that he is a person with mental retardation , and thus ineligible for the death penalty , '' said Kammer . Hill 's lawyers say his low IQ means he should be spared under a 2002 decision that barred the execution of the mentally disabled . A string of state courts has said Hill does n't qualify under Georgia law , which requires inmates to prove mental impairment `` beyond a reasonable doubt . '' CNN 's Matt Smith and Dana Ford contributed to this report .
Warren Hill had been scheduled to die Monday night . The shooting happened at a home in the 5300 block of South Kedzie Avenue about 10:45 p.m. Monday. The state says that has n't been proven in court .