The setting is Iran, and it concerns a young woman who had spurned the approaches of a man. His response was to throw acid in her face which has left her disfigured and blind. You can read about it here.
Under the Sharia code of qias or equivalence the victim can ask that the guilty party be punished in a like manner. The court accepted her plea and the man has been sentenced to be blinded by acid, though I don't believe that the punishment has yet been carried out.
This seems barbaric, but then so was the attack, and it is far too common in the middle east and asia. The acid is usually battery acid, and thus very easy to get hold of, and it is not the sort of attack you can carry out without premeditation.
These are the kinds of injury that commonly occur. The photograph is of a different woman, injured by her husband after they were divorced.
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Other recent attacks have been on schoolgirls in Afghanistan, whose only crime is that they want to go to school.
In the West we would argue that violence is an inappropriate response to violence, or that such punishment reduces the state to the level of the criminal. But should we be liberal and intellectual about such crimes? These men are absolute bastards. Is there an argument for an eye for an eye?