International humanitarian law
The Geneva Conventions, of which there are four, are considered universal treaties in international law. They created the idea of International humanitarian law and codify customary international law regarding laws in wartime. By signing parties agreed to criminalise any breaches in their own domestic courts, U.S recognised this when they enacted their own War Crimes Act. However the declaration made by Bush in 2002 had the effect of 'exempting all alleged members of Al Qaeda from the protections of the Geneva conventions'.