Spoils is the term used by Shadowhunters to refer to the possessions and wealth of a Downworlder taken as part of the punishment for a crime. A controversial practice, the taking of spoils has been illegal since the signing of the Accords.
Spoils were either claimed by the Shadowhunter who has been wronged, or forfeited to the Clave, which can then either be kept in the Clave's treasury, or granted to a Shadowhunter, which was the most common case. Apparently, a good portion of the riches of many old, wealthy Shadowhunter families originate from spoils.
The awarding of spoils were first mentioned in Clave records around 1400. Spoils was a popular form of punishment for Downworlder offenses until the signing of the First Accords which, although did not eliminate spoils completely, strongly restricted the severity of the punishment, and also provided that the punishment of taking spoils from Downworlders could be executed only as part of an official sentence at a trial performed by the Clave.
During the time when the prohibition of spoils were still just reforms, the proposals were opposed heavily by some Shadowhunter families, particularly those strongly dependent on spoils for their wealth and stood to lose quite a lot, argued that the rules restricting spoils would harm the Clave directly as the wealthier families tend to tithe a percentage of their spoils to the Clave.
Many spoils have since been returned in the past hundred years, although those which haven't are placed on display in various Institutes, as historical curiosities. In the 1870s, Aloysius Starkweather had an entire room that displayed all his spoils in the York Institute.