John Joseph Connolly Jr. is an American former FBI agent who was convicted of racketeering, obstruction of justice, and murder charges stemming from his relationship with James "Whitey" Bulger, Steve Flemmi, and the Winter Hill Gang.

James Joseph "Whitey" Bulger Jr. was an American organized crime boss who led the Winter Hill Gang in the Winter Hill neighborhood of Somerville, Massachusetts, a city directly northwest of Boston. On December 23, 1994, Bulger fled the Boston area and went into hiding after his former FBI handler, John Connolly, tipped him off about a pending RICO indictment against him. Bulger remained at large for sixteen years. After his 2011 arrest, federal prosecutors tried Bulger for nineteen murders based on grand jury testimony from Kevin Weeks and other former criminal associates.