Is a Muslim liable for retribution (Qisas) if they killed or injured an unbeliever before accepting Islam and subsequently embraced Islam?
General Chapter
Al-Mughni
Book of Wounds
Primary text
Retribution is required against the killer who was a non-believer at the time of the act but subsequently embraced Islam, or who was a non-believer when inflicting an injury which subsequently resulted in death. This is the position held by our companions and Imam Al-Shafi'i. Retribution is considered a punishment, and its consideration is based on the state at which it became obligatory, not the state at which it is carried out, similar to the penal limits (Hudud). Furthermore, it is a right that became incumbent upon him before his conversion and is not nullified by his Islam, just like a debt.
Supporting text
There is an opposing view, held by Al-Awza'i, that he should not be subject to retribution. This is based on the Prophetic statement: 'A Muslim is not killed for a non-Muslim.' Additionally, the principle holds that a believer is not killed for a non-believer, the same as if he had been a believer at the time of the killing. If his conversion had coincided with the cause of death, the act would have been prevented; therefore, its subsequent occurrence nullifies its effect.