'How can you stay sane when all you hear, see or smell is desperation, fear, death? I've seen hundreds of them walk down this hallway for the last time; some guilty, some innocent.'

Anthony Graves faced execution in Texas for 18 years before he was cleared of the crime that put him there. This is his story.

152 people have been exonerated from America's death row since 1973 - cleared of the crimes that they were due to die for. We do not know how many people have been executed for crimes they did not commit.

The death penalty is a flawed and irreversible system, which is why we're campaigning for an end to its use around the world.