Is a thief subject to amputation (Qat') for stealing from a relative?
Chapter on Amputation in Theft
Al-Mughni
Book of Ḥudūd (Prescribed Penalties)
Primary text
Amputation is mandatory for stealing the property of relatives such as brothers, sisters, and others among kin, and they are subject to amputation for stealing one's property. This is the position held by Al-Shafi'i. The evidence supporting this is that kinship does not prevent bearing witness (testimony), thus it should not prevent the penalty of amputation, unlike the kinship related by direct descent (birth relation).
Supporting text
Abu Hanifa holds that amputation is not carried out for theft committed against a close relative because such kinship prevents marriage, permits looking (upon one another), and obligates maintenance, making it analogous to the kinship related by direct descent (birth relation).