Jeff Hood, a pastor who has accompanied condemned inmates for 15 years, says he has witnessed 12 executions, including Alabama's closely watched nitrogen gas cases.
Inside the chamber, Hood says his role is to pray, offer physical comfort and ensure inmates do not die alone after trials and appeals have ended.
His eyewitness account of Alabama's first nitrogen hypoxia execution has fed a wider fight over whether the method is a constitutional alternative or an inhumane practice.
Hood says the impact reaches beyond the condemned, affecting prison staff, lawyers, victims' families, clergy and communities as Alabama's protocol draws national scrutiny.