The agent, now 64, formally interviewed McIntyre in October 1984, with an FBI agent who he said knew John Connolly, Bulger's rogue FBI handler who is now imprisoned. The prosecution charges that Bulger ordered a hit on McIntyre when he learned he was cooperating with authorities
Though DeFago testified that McIntyre named dozens of organized crime associates responsible for the seaborne marijuana exchanges, he never once named Bulger or his No. 2, Stephen "The Rifleman" Flemmi.
McIntyre said it was Pat Nee, a reputed Charlestown gangster, who was the head of the jobs. DeFago said he "understood that Whitey and Flemmi were apart of Nee's crowd."
Bulger's alleged No. 2 takes stand Thursday
Sparks are likely to fly Thursday when Flemmi, nicknamed "The Rifleman," takes the stand.
Defense attorneys say Bulger heard that Flemmi was arrested on extortion charges in 1995 on the radio and decided to go on the run for 16 years, landing himself on the FBI's most-wanted list before being arrested with his girlfriend in their Santa Monica, California, apartment in 2011.
Flemmi argued he had immunity and should be exonerated of charges because he was an FBI informant. A judge ruled he did not have immunity, and he was sentenced in August 2001 to 10 years in prison for extortion and money laundering as part of a plea agreement.
The government's star witness was once Bulger's front man for the "Winter Hill Gang," collecting money from bookies and inspiring fear in those that didn't pay their debts.
Flemmi pleaded guilty to 10 murders after charges were brought in 2004 and was spared the death penalty after agreeing to testify against Bulger.
The two will be reunited Thursday for the first time in 18 years.
Prosecutors say Flemmi's testimony will be the nail in the coffin in locking up the Bulger case.