Does Qasamah apply when the killer is someone upon whom Qisas is not otherwise obligatory, such as a Muslim killing a disbeliever, or a free person killing a slave?
Chapter on Qasamah (Oaths regarding murder)
Al-Mughni
Book of Blood-Money (Diyyāt)
Primary text
If the killer is someone upon whom *qisas* is not obligatory, such as a Muslim killing a disbeliever, or a free person killing a slave, there is no Qasamah according to the apparent view of Al-Kharqi and the view of Malik, because Qasamah is only established for cases that mandate *qisas*. The supporting evidence is that since Qasamah is legislated for a killing that mandates *qisas*, it is not legislated for a killing where *qisas* is absent, as demonstrated when a slave is accused of killing his master; Qasamah is only legislated if the killing mandates *qisas*, because the slave cannot be executed otherwise.
Supporting text
The view of Al-Qadi and Al-Shafi'i, and the People of Opinion, is that Qasamah is established in these cases because it involves the killing of a human being that necessitates expiation (*kaffarah*), thus Qasamah is legislated, similar to the killing of a free Muslim. Furthermore, what serves as evidence in the killing of a free Muslim should serve as evidence in the killing of a disbelieving slave, similar to ordinary testimony (*bayyinah*).