What is the ruling regarding a usurper who alters the usurped item by adding a feature, such as dyeing it?
Chapter on Amputation in Theft
Al-Mughni
Book of Ḥudūd (Prescribed Penalties)
Primary text
If the usurper adds to the item, such as dyeing it red or yellow, the item must not be returned to the owner, and the usurper is not permitted to dispose of it. Abu Yusuf and Muhammad maintain that the item must be returned, arguing that refusing return due to potential co-ownership via dyeing is invalid, especially if the dyeing occurred before any damage (cutting) that might imply co-ownership.
Supporting text
Abu Hanifa states the item should not be returned because dyeing it would make the usurper a partner in it, and one cannot claim compensation for what one is a partner in. However, this is contradicted by his view that if one steals silver and strikes it into dirhams, the cutting is obligatory and return is required.