A federal judge has permanently blocked Alabama from executing Jeffery Lee using nitrogen gas, ruling that the method violates constitutional protections against cruel and unusual punishment. The decision came just days before Lee's scheduled execution Thursday at an Alabama prison.

Judge Emily C Marks issued the 26-page ruling on Tuesday, reversing her own earlier decision from May 29 that had allowed the execution to proceed. At that time, Marks had cited testimony from three medical experts stating that "air hunger" caused by nitrogen hypoxia did not constitute an unconstitutional level of pain.

However, on June 8, a three-judge panel from the 11th Circuit Court of Appeals reversed Marks's initial order. The appeals court determined that Alabama's nitrogen hypoxia protocol presented "a substantial risk of serious harm" involving severe pain beyond what is necessary to carry out a death sentence. The panel directed Marks to reconsider the case.

In her new ruling, Marks acknowledged that Alabama has two other authorized execution methods available: lethal injection and the electric chair. She stated that Lee is "not entitled to an injunction barring the state from executing him using one of those methods."

Alabama became the first state in the nation to carry out a nitrogen gas execution in January 2024. The method has faced repeated legal challenges since its introduction. The first such execution involved Kenneth Eugene Smith and lasted 22 minutes. A journalist who witnessed the execution reported to the BBC that Smith thrashed in a way she had never seen before during four previous executions she had attended.

Lee's case has garnered significant attention partly because of the unusual circumstances surrounding his sentencing. In 2000, a jury voted to sentence him to life without parole for murders committed in 1998. However, a judge overrode the jury's recommendation and imposed a death sentence instead. Alabama later banned judicial override in new cases when Governor Kay Ivey signed legislation in 2017, but the law did not apply retroactively to past cases like Lee's.

Lee's legal team has requested that Governor Ivey grant him clemency and eliminate judicial override retroactively. A spokeswoman for Lee's legal team said they had no immediate comment on the ruling.

Alabama's attorney general's office announced it would appeal the decision. Legal experts expect the case will likely reach the United States Supreme Court, which has previously allowed nitrogen executions to proceed.

In her ruling, Marks wrote that litigation over execution methods is constant in death penalty cases. She noted that any execution method, regardless of how humane, would likely face constitutional challenges, and that the Constitution does not guarantee a painless death.