An Arkansas inmate scheduled to receive a lethal injection this week asked the state's highest court Monday to halt his execution amid his attorneys' claims that he doesn't understand why he is to be put to death.

Attorneys for Jack Greene asked the state Supreme Court to issue an emergency stay of execution. Greene is scheduled to be executed Thursday night for the 1991 death of Sidney Burnett, who was beaten with a can of hominy, stabbed and later shot.

Greene's attorneys asked for the stay while they appeal a lower court's dismissal of their lawsuit challenging an Arkansas law giving the state's top prison official the authority to determine whether Greene is competent to be executed. Greene's attorneys say he suffers from psychotic delusions, and say the inmate believes the attorneys and prison officials have conspired to torture him.

The judge who dismissed the suit said the law had already been upheld as constitutional and that she didn't have the authority to stay the execution.

The filing cited the court's decision to halt the execution of another inmate, Bruce Ward, in April over similar claims about his mental competency.

"The court should not allow the state to avoid the substantial questions presented here by executing Greene before the court can address them — as it has already committed itself to do in another case," Greene's attorneys said in Monday's filing.