Physicians in Islamic countries might be requested to participate in the Islamic legal code of qiṣāṣ, in which the victim or family has the right to an eye-for-an-eye retaliation. Qiṣāṣ is only used as a punishment in the case of murder or intentional physical injury. In situations such as throwing acid, the national legal system of some Islamic countries asks for assistance from physicians, because the punishment should be identical to the crime. The perpetrator could not be punished without a (...) physician’s participation, because there is no way to guarantee that the sentence would be carried out without inflicting more injury than the initial victim had suffered. By examining two cases of acid throwing, this paper discusses issues related to physicians’ participation in qiṣāṣ from the perspective of medical ethics and Islamic Shari’a law. From the standpoint of medical ethics, physicians’ participation in qiṣāṣ is not appropriate. First, qiṣāṣ is in sharp contrast to the Hippocratic Oath and other codes of medical ethics. Second, by physicians’ participation in qiṣāṣ, medical practices are being used improperly to carry out government mandates. Third, physician participation in activities that cause intentional harm to people destroys the trust between patients and physicians and may adversely affect the patient–physician relationship more generally. From the standpoint of Shari’a, there is no consensus among Muslim scholars whether qiṣāṣ should be performed on every occasion. We argue that disallowing physician involvement in qiṣāṣ is necessary from the perspectives of both medical ethics and Shari’a law. (shrink)