At the Death House Door is a personal and intimate look at the Death Penalty in the state of Texas through the eyes of Pastor Carroll Pickett, who served 15 years as the death house chaplain to the infamous “Walls” prison unit in Huntsville. During Pickett’s remarkable career journey, he presided over 95 executions, including the world’s first lethal injection.
After each execution, Pickett recorded an audiotape account of his trip to the death chamber.
The film also focuses on the story of Carlos De Luna, a convict Pickett counseled and whose execution troubled Pickett more than any other. He firmly believed De Luna was innocent, and the film tracks the investigative efforts of a team of Chicago Tribune reporters who have turned up evidence that strongly suggests he was.
From what I've read, that description doesn't do it justice... You can see the whole special by downloading here.