The state of Alabama executed inmate Alan Eugene Miller with nitrogen gas on Thursday, making him the second to die under the controversial capital punishment method.
Miller, 59, was sentenced to death in 2000 for shooting dead three of his former colleagues in 1999.
A previous attempt to execute Miller in 2022 was called off when authorities were unable to access his veins. Thursday’s execution followed a lawsuit in which Miller claimed nitrogen gas could cause him excessive suffering, violating the Eighth Amendment’s protections against cruel and unusual punishment.
Alabama Attorney General Steve Marshall said the settlement was proof that the method — which was first used to execute Kenneth Smith earlier this year — was constitutional.
Proponents of the method – nitrogen hypoxia – argue that it causes a person to quickly lose consciousness when breathing 100% nitrogen instead of oxygen. However, doctors said it was virtually impossible to determine when someone lost consciousness during the execution.
Critics have said that dying from nitrogen hypoxia is tantamount to being tortured to death, as it can cause excessive pain while the person suffocates.
Witnesses to the execution reported that he shook on a stretcher for several minutes before dying. Witnesses to Smith’s execution reported similar observations.
“Everything went according to plan and according to our protocol,” Alabama Department of Corrections Commissioner John Hamm told reporters after Miller’s death.
Louisiana, Oklahoma and Mississippi have also authorized the use of nitrogen gas in executions, but have not yet used it.
