Paul McGonagle

Following the murder and subsequent disappearance of her husband Paul, Margaret was granted a divorce, on grounds of abandonment, and remarried, to a man named McCusker, to whom she was still married as of 2008.

In September 2003 a body was found among other bodies in Boston that was thought to have been the remains of McGonagle, but this has not been proven to be true.

It has since been revealed by investigators that Bulger was responsible for McGonagle's disappearance in November 1974. It was likely for this reason that Bulger either shot or ordered McGonagle to be shot in the head and buried him in a shallow grave on Boston's Tenean Beach. The murder was almost certainly sanctioned by Howie Winter. At the time of McGonagle's murder in 1974, his estranged wife Margaret was left a widow.

During the Killeen-Mullen gang war, McGonagle and Irish immigrant Patrick Nee successfully led the Mullens against the Killeen brothers' organization, which finally ended when the neighbourhood boss Donald Killeen was gunned down outside his suburban home in 1972. The leadership of the Killeen Gang then devolved on Whitey Bulger.

Paul's younger brother Donny lived a law-abiding life and did not follow his brother into a life of organized crime. Donald, however, who shared a fleeting physical resemblance with his brother, was mistaken by Bulger to be Paul and was shot in the head, execution style, in 1971, (an alternative version of events, according to the opposing gang, is that Donald was shot in the face while driving, by another motorist - James "Whitey" Bulger) during the Killeen-Mullen gang war. The FBI stated on their wanted fugitive poster of Catherine Greig that one of the aliases she was known to have used in 1995 before she fled with Bulger was "Catherine McGonagle", taking the last name of her slain brother-in-law as her own after going on the run with Bulger.

While in South Boston, he married Margaret Greig (born April 3, 1951), from East Boston, identical twin sister of Catherine Elizabeth Greig, wife of his brother Bobby. They had two sons, Paul Jr. and Sean McGonagle. The Greig sisters had a younger brother David. McGonagle and Margaret moved into a home in suburban Quincy, Massachusetts, where she lived during their marriage. Sister-in-law Catherine later divorced Bobby before taking up with Winter Hill Gang leader James J. Bulger.

Paul McGonagle Sr. (January 21, 1939 – November 1974) was an Irish-American mobster and leader of the Mullen Gang, a South Boston street crew involved in burglary and armed robbery.