Slate has a brutally honest account of what happens when a person is sentenced to death via stoning.
First, you get buried. Iran’s Islamic Penal Code states that men convicted of adultery are to be buried in the ground up to their waists; women, up to their chests. If the conviction is based on the prisoner’s confession, the law says, the presiding judge casts the first stone. If the conviction is based on witness testimony, the witnesses throw the first stones, then the judge, then everyone else—generally other court officials and security forces. Stones must be of medium size, according to the penal code: Not so big that one or two could kill the person, but not so small that you would call it a pebble. In other words, about the size of a tangerine. The whole process takes less than an hour.
One possible upside of getting stoned is that people who manage to escape from the hole are allowed to go free. But this applies only to those who have confessed to their crimes. (If you were sentenced to stoning on the basis of witness testimony, then digging out of the hole does you no good.) In any case, it’s very difficult for anyone to escape the punishment: Prisoners are wrapped in a white cloth sack with their hands tied.
Allow me this tangent: Has anyone else ready Shirley Jackson’s short story The Lottery? Probably one of my five favorite short stories.