The Supreme Court has ruled that Alabama can move forward with plans to execute a death row inmate using nitrogen gas — a method of execution by asphyxiation that has never been used in the United States.
The court denied a stay of execution on Wednesday for Kenneth Smith, who was sentenced to death in 1989 for the murder of Elizabeth Sennett, and was already subjected to a botched attempt at execution by lethal injection in 2022. In May of last year, the Supreme Court denied an appeal by state officials to once again attempt to execute Smith through lethal injection.
Death through nitrogen hypoxia, which would occur through the forced inhalation of high concentrations of nitrogen gas, is an untested method of execution. Attempts to use the method to euthanize mammals with the method have been rejected by the American Veterinary Medical Association under findings that the gas can be “distressing for some species.”
Smith would be strapped to a gurney in the execution chamber and fitted with a mask that would feed the gas into his lungs. The increased concentration of nitrogen in Smith’s blood would cause asphyxiation and organ death. Attorneys for Smith have argued that since the procedure has never been tested on a human, the state runs the risk of botching the execution, leaving Smith potentially braindead or with severe physical injuries, as well as violating constitutional protections against cruel and unusual punishments.
Concerns have also been raised that the possibility of a gas leak within the chamber could place the executioners, other correctional staff, and witnesses at risk given the toxic nature of nitrogen as well as its high flammability.
Earlier this month, the United Nations Office of the High Commissioner for Human Rights called on Alabama to halt the execution, citing “serious concerns” that their plan and lack of provisions for sedation and contingencies “could breach the prohibition on torture or other cruel, inhuman, or degrading treatment or punishment, as well as his right to effective remedies.”
“The death penalty is inconsistent with the fundamental right to life,” the commission wrote. “There is an absence of proof that it deters crime, and it creates an unacceptable risk of executing innocent people. Rather than inventing new ways to implement capital punishment, we urge all States to put in place a moratorium on its use, as a step towards universal abolition.”
