The US Supreme Court stepped in on Tuesday before Missouri could execute a man who was considered mentally disabled even before a fifth of his brain was removed. Ernest Lee Johnson, 55, was sentenced to death for killing three convenience store workers with a claw hammer during a 1994 robbery, but lawyers argue that a lethal injection drug could cause painful seizures because of a brain tumor and a hole in his head, the AP reports. Surgery in 2008 left Johnson with the hole in his skull and removed a large portion of brain, but it left part of the tumor behind. His lawyers say the "severely painful" execution with a dose of pentobarbital would constitute cruel and unusual punishment, NBC News reports.
The Supreme Court told the 8th US Circuit Court of Appeals to reconsider its decision not to stay the execution because Johnson did not prove he would suffer pain and failed to offer an alternative execution method, reports the Columbia Daily Tribune. His death warrant expires at 6pm Wednesday, and a Missouri Department of Corrections official says there is "no indication of any kind that this is going to be resolved" before then, the AP reports. After his conviction, testing found that Johnson had an IQ of 67, and a separate appeal before Missouri's Supreme Court argues that he is mentally disabled and it would be unconstitutional to execute him, the Tribune reports. (The state executed a brain-damaged former sawmill worker earlier this year.)