Is a pardon granted to a deliberate killer absolutely valid, absolving them of further punishment?

Primary text

A pardon granted to a deliberate killer (*qātil*) without condition is valid, and no further punishment is incumbent upon them. This ruling is held by Al-Shafi'i, Ishaq, Ibn al-Mundhir, and Abu Thawr. The basis for this is that only one right was incumbent upon the killer, and its rightful owner has waived it. Therefore, nothing else is obligatory, just as if the blood money (*diyya*) for accidental killing were waived.