Iran has an “eye for an eye” system of punishment for criminals.
Iranian criminal law has its basis in 7th-century traditional Islamic law. One of the aspects of this system that has continued into modern times is the principle of qesas. Qesas allows for victims of crimes to seek retribution by having the same crime perpetrated against the accused. This is literally the concept of “an eye for an eye” put into practice.
This practice has put Iran at odds with the international public and human rights organizations. Iran doesn’t consider the death penalty for murderers to count as execution because it falls under the category of qesas. For this reason, they have no problem with with giving the death penalty to children if the children have been accused of murder. Also, in a well-publicized case, a woman who had acid thrown in her face had to make a choice between two unattractive options. Under the law, she had the option to either let her attacker off without punishment or to have him be punished under qesas. In this case, the qesas punishment would have the woman punish her attacker by pouring acid on his face. She didn’t have the option to put her attacker behind bars instead.