What is the ruling regarding the amputation of a hand or foot for a person who already has only one functioning hand or foot?
Chapter on Diyat (Blood Money) for Wounds
Al-Mughni
Book of Blood-Money (Diyyāt)
Primary text
If one hand or foot is severed from a person who already lacks one of that corresponding limb, half the full blood money (Diyah) or retaliation (Qisas) for an identical limb is incumbent. This is because the remaining limb is a single organ from a pair necessary for the complete function of the type of limb, and thus compensation is proportional, similar to severing one ear from a person with only one ear. This ruling is supported by the general principle that for members where a full Diyah is due for both, half Diyah is due for one, as seen with hands and fingers. Furthermore, if a portion of that remaining limb is severed, compensation is due proportional to that portion of half the Diyah.
Supporting text
An alternative narration from Ahmad suggests that if the first limb was severed unjustly and its Diyah was taken, or it was severed as Qisas, the remainder carries half Diyah. However, if the first limb was severed in the path of God (fi sabilillah), the remaining limb warrants a full Diyah, analogous to the complete loss of function from two organs, like the loss of one eye for a blind person. This view is rejected because the two eyes, unlike the hand and foot, do not significantly differ in essence or ruling, and the judgment regarding the eye of a blind person is inapplicable due to three reasons: the eye of the blind provides the full function of an eye; the ruling on the eye of the blind does not change based on how the first eye was lost, unlike the hand/foot scenario; and establishing specific fractional compensation without textual basis or clear analogy is deemed mere arbitrary ruling.