By Lawrence Hurley

WASHINGTON (Reuters) – The U.S. Supreme Court on Monday refused to let a Missouri death row inmate with significant health problems pursue his effort to face execution by firing squad instead of lethal injection.

The justices, with the three liberals on the nine-member conservative-majority court dissenting, turned away the appeal brought by Ernest Johnson, who has epilepsy prompted by a brain tumor and further damage to his brain caused by a surgical procedure.

Johnson, sentenced to death for three murders he committed during a 1994 gas station robbery, said that execution by lethal injection would cause significant pain in violation of the U.S. Constitution’s Eighth Amendment, which bars cruel and unusual punishment. He sought death by firing squad instead on the grounds it would be less painful.

“Missouri is now free to execute Johnson in a manner that, at this stage of the litigation, we must assume will be akin to torture given his unique medical condition,” liberal Justice Sonia Sotomayor wrote.

(Reporting by Lawrence Hurley; Editing by Will Dunham)