Boston hitman Joseph 'The Animal' Barboza was the first person in American history to enter witness protection, but the deal with the Devil ended as 'one of the greatest failures' in FBI history when he was hunted down in San Francisco
Shot dead on the streets of San Francisco almost a half-century ago, his reputation as an enforcer persists - along with his decision to flip to the FBI that thrust him into witness protection.
Source: dailymail.co.uk