Arizona’s preparation to use lethal gas comes amid a scarcity of execution drugs and as other states have taken a closer look at firing squads and other execution methods.
Lethal gas is permitted for executions in six other states: Alabama, California, Mississippi, Missouri, Oklahoma and Wyoming. Oklahoma, Mississippi and Alabama have authorized nitrogen hypoxia, which uses nitrogen to deprive the body of oxygen, despite a small body of scientific research and no previous executions using the method in the United States.
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