His testimony is viewed as responsible for the convictions of FBI agent John Connolly, as well as forcing Bulger's right-hand man, Stephen Flemmi, to plead guilty as well.

[1] Kevin Weeks was born in South Boston, Massachusetts, on March 21, 1956, to a working-class family of Irish and Welsh descent.

Impressed by Weeks' knack for making money and genuinely liking him, Bulger decided to bring him in closer than any other associate.

[3] On the night of May 11, 1982, Bulger was told of the whereabouts of a former associate turned federal informant, Brian Halloran, known on the streets as "Balloonhead" owing to the size of his cranium.

[4] After arriving at the scene, Weeks staked out Anthony's Pier 4 Restaurant, where Halloran and construction worker Michael Donahue were dining together.

As Donahue and Halloran drove out of the parking lot in a blue Datsun, Weeks signaled Bulger by stating, "The balloon is in the air", over a handheld radio.

Bulger and the other shooter, allegedly Pat Nee, opened fire and sprayed Halloran and Donahue's car with bullets.

As Halloran stumbled out of the car, Bulger continued to shoot him as his writhing body was "bouncing off the ground", according to Weeks.

[4] Weeks described the murders of Halloran and Donahue as the event which cemented his association with Bulger, saying: "I was involved in a double homicide, so I knew there was no getting out".

During the 1980s, Weeks operated several convenience stores and liquor marts in South Boston that served as fronts for the Winter Hill Gang.

He collected payments from loan sharks and bookmakers, insulating Bulger from the transactions, and also helped extort local criminals and businessmen who were behind on their debts to the gang.

"[4] In 1983, Weeks and O'Neil acquired Stippo's Liquor Mart in South Boston from owners Stephen and Julie Rakes by using threats of violence.

In 1998, Stephen "Stippo" Rakes was convicted of perjury and obstruction of justice for telling grand juries that the sale of the liquor store was voluntary.

[7] In order to avoid electronic eavesdropping, Weeks, Bulger and Flemmi discussed business during long walks in public places including Castle Island, a circular path in South Boston known as the Sugar Bowl, and Columbia Park, which was adjacent to the liquor store which served as one of Bulger's offices.

We never dealt with the street dealers, but rather with a dozen large-scale drug distributors all over the State who were bringing in the coke and marijuana and paying hundreds of thousands to Jimmy.

[2]: 152 In South Boston, most of the neighborhood's drug trade was managed by a handpicked crew of prize fighters led by John Shea.

[2]: 16 Weeks also insists that Bulger strictly forbade PCP and selling to children,[2]: 179  and that those dealers who refused to play by his rules were violently driven out of the neighborhood.

[2]: 248 On November 17, 1999, Weeks, O'Neil, and other Winter Hill associates were arrested in South Boston by agents of the Drug Enforcement Administration (DEA), the Massachusetts State Police and the Internal Revenue Service (IRS).

[8] The next afternoon, he was presented with a 29-count indictment under the Racketeer Influenced and Corrupt Organizations Act (RICO), which alleged extortion, money laundering and drug trafficking.

Prosecutors were outraged at Winter Hill's crime spree, and were also frustrated when IRA sleeper associate James "Gentleman Jim" Mulvey refused to flip.

In addition, Weeks was also deeply impressed by the cooperation of John Martorano, a legendary enforcer for the Winter Hill Gang.

[11] In 2000, he led authorities to six different bodies buried by the Winter Hill Gang, including the triple grave of Hussey, McIntyre and Barrett, as well as a cache of weapons in Flemmi's home in South Boston.

[11] Jackie was sentenced to six months in federal prison for lying to a grand jury about his actions, while Billy was forced to resign as president of the University of Massachusetts.

[12] Weeks also testified against two of Bulger's friends in law enforcement; Special Agent Connolly and Lieutenant Richard J. Schneiderhan of the Massachusetts State Police.

[11] Kevin Weeks married his longtime girlfriend, Pamela Cavaleri (born 1957), on April 26, 1980 at the Gate of Heaven Roman Catholic Church in their native South Boston.

[4] At a book signing in April 2006, Kevin Weeks told the crowd at a Boston Barnes & Noble that he once intended to return to being a gangster once he was released from prison.