US Supreme Court refuses to block execution of man using untested nitrogen gas

The US Supreme Court has rejected a request for a stay of execution from a death row inmate in Alabama after he objected to the untested method of nitrogen gas being his method of execution.

Kenneth Smith, sentenced to death in 1988 for the murder of Elizabeth Sennett, objected to the method of execution on the grounds that the state of Alabama might botch the procedure.

He claimed that the untested method would violate his right to be free of cruel and unusual punishment.

The US has never executed anyone using nitrogen gas before, and the last time they killed a prisoner with lethal gas was in 1999.

Smith's execution is scheduled to be carried out tomorrow (25 January), though he has a separate claim pending in another court that could see his execution called off.

Alabama Department of Corrections

According to NBC, the Supreme Court last year rejected the state of Alabama's bid to execute Smith via lethal injection against his wishes.

The death row inmate had objected to lethal injection by saying it would cause him pain and, just as he now objects to with the nitrogen gas, violate his right to be free of cruel and unusual punishment.

When rejecting the lethal injection, Smith had suggested gas as an alternative method of execution instead.