William "Billy" Stobie (1950 – 12 December 2001) was an Ulster Defence Association (UDA) quartermaster and RUC Special Branch informer who was involved in the shootings of student Adam Lambert in 1987 and solicitor Pat Finucane in 1989. His 1990 admissions, to journalist Neil Mulholland, provided new information which led, in February 1999, to submitting a confidential report to the British Government. This in turn would lead to the reopening of the Stevens Enquiry, which uncovered state/paramilitary collusion at a level "way beyond" what Sir John Stevens had originally reported.