"Amnesty International has urged Iran to drop from its penal code the punishment of death by stoning, a fate awaiting 11 convicted criminals, the group says."
This is how careful the Iranian penal code is:
It "stipulates the stones used must be large enough to cause the condemned pain, but not sufficient to kill immediately."
Islam stipulates that when you slaughter an animal for food, you do it without inflicting undue suffering on the beast. This law of mercy doesn't apply to humans, according to Iranian interpretations.