UN raises concerns over 'untested' nitrogen hypoxia execution, set for Alabama

United Nations experts are sounding the alarm over the planned execution of an Alabama inmate by nitrogen gas, arguing it is an "untested" method that could subject the inmate to "cruel, inhuman or degrading treatment" or torture.

In a report issued Wednesday, a panel of U.N. experts — part of the Human Rights Council's special procedures program — noted the expected execution of Kenneth Eugene Smith will be the first attempt of its kind with the possibility of "grave suffering."

The warning comes nearly two months after the Alabama Supreme Court ruled the Yellowhammer State can execute an inmate with nitrogen hypoxia. An execution of this style would deprive the inmate of the oxygen needed to maintain bodily functions. Nitrogen makes up 78 percent of the air inhaled by humans and is harmless when inhaled with oxygen.

“We are concerned that nitrogen hypoxia would result in a painful and humiliating death,” the experts wrote in a statement, adding experimental executions by gas asphyxiation — like nitrogen hypoxia — "will likely violate the prohibition on torture and other cruel, inhuman or degrading punishment."

Smith's execution is slated for Jan. 25 and would make Alabama the first state in the U.S. to attempt at an execution with nitrogen gas.

The Alabama ruling last year was in response to the state attorney general's request for Smith's execution, one of two men convicted in the 1988 murder-for-hire killing of Elizabeth Sennett in Alabama's Colbert County.

Those in support of the nitrogen gas method have argued the execution is painless, and the Alabama attorney general noted in his request last year that Sennett's family has waited "an unconscionable 35 years to see justice served."

The U.N. experts said they appealed to U.S. federal authorities and those in Alabama to halt Smith's execution and others scheduled for this procedure until the execution protocol is reviewed.

Alabama already had paused its executions in 2022 after reports of failed executions by lethal injections.

Last year, the U.S. Supreme Court sided with Smith after he challenged the state's decision to execute him by lethal injection. The nation's highest court, however, declined to review a lower court’s ruling that affirmed Smith’s right to die by lethal gas rather than injection.

At the time of last year's ruling, Alabama had approved the use of nitrogen gas but had not yet finalized the protocols for its application.