The US Supreme Court declined to hear an appeal Monday from a death row inmate who sought to have his sentence carried out by firing squad because he believes it would be less painful than the state’s preferred method of execution.

Ernest Johnson, a death row inmate in Missouri, suffers from epilepsy as a result of a brain tumor and damage caused by significant brain surgery. In a complaint filed in 2016, Johnson alleged that he will experience excruciating seizures if Missouri executes him by lethal injection of the drug pentobarbital. However, the US Court of Appeals for the Eighth Circuit pointed to the Supreme Court’s decision in Bucklew v. Precythe, holding that an inmate who wants to challenge the use of a method of execution in his particular case must identify a feasible alternative that will “significantly reduce a substantial risk of severe pain,” to reject Johnson’s request.

In her dissent, Justice Sonia Sotomayor found “the Eighth Circuit’s decision punishes Johnson for failing to anticipate significant changes in the law brought about by Bucklew. Worse, it ensures that Johnson’s claim will never be heard on the merits.” “Missouri,” Sotomayor concluded, “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.”

The Supreme Court will meet again for another private conference on Thursday, May 27, and orders from that conference are expected on Tuesday, June 1.