Notorious Boston underworld kingpin James "Whitey" Bulger was jailed for life on Thursday after a 40-year career of murder, money laundering and arms trafficking.
Bulger, 84, who was arrested in 2011 after 16 years on the run, faces the prospect of dying in prison after Judge Denise Casper handed down two life terms and an additional five years in prison.
Casper, who also ordered Bulger to pay just over $19.5 million in restitution to his victims, branded the feared mobster's catalogue of crimes as "unfathomable."
Bulger, a former FBI informant, said only one word after sentencing: "yes" when asked if he understood.
It was a dramatic end to the career of a man who provided the inspiration for Jack Nicholson's mob boss character in Martin Scorsese's Oscar-winning 2006 gangster film "The Departed."
Tom Donahue, whose father was murdered by Bulger, welcomed the verdict as offering "some closure".
"To hell with him, next time I want to hear about him is that he's dead," he said.
A 12-person jury in August found the Irish-American octogenarian guilty of 31 separate charges that included 11 murders, extortion, money laundering and arms trafficking.
Casper, who has won widespread praise for the aplomb with which she handled the two-month trial and enormously complex case, described Bulger's crimes as "heinous."
"The motivation of your entire criminal history is based on money. It takes no business acumen to stick a gun in somebody," she told the US district court in Boston.
She read out the names of the 11 victims he was convicted of murdering and said it was impossible to know where to begin when faced with Bulger's four-decade reign of crime.
"At times during the trial I wished we were watching a movie but it was real," she said.
Bulger sat impervious, wearing his short-sleeved, orange cotton jail uniform with a white, long-sleeved jersey underneath. He wore glasses was clean shaven.
"Your motivation behind these crimes or your entire criminal history is based upon money. Your crimes are all the more heinous because they were about money," Casper said.
She said many of his victims' loved ones were still suffering and pointed out many had to wait years to find out how they died.
"The loss of a loved one is pain enough but to lose someone to violence is unimaginable," Casper said.
She also gave voice to claims that other people are guilty.
"I considered you did not accomplish all your crimes by yourself and certainly you did have some FBI people in your pocket."
The trial, which featured 72 witnesses and 840 exhibits, produced chilling testimony worthy of a pulp novel.
It heard harrowing tales of teeth being pulled from the mouths of murder victims to foil their posthumous identification and the fatal strangulation of a mobster's girlfriend who "knew too much."
Bulger refused to testify at his trial, saying the proceedings were "unfair and a sham" because it would not recognize what he claimed was immunity from prosecution given by federal agents.
Casper said she had "struggled" with what would be just punishment for the nature and scope of his crimes, but dismissed Bulger's complaints of a sham trial.
"Call it what you want, but in my estimation you received a fair trial," she said.
His lawyers said they would appeal the conviction.
Bulger always denied being an FBI informant, but close links between some FBI agents in Boston and Bulger's Winter Hill Gang in the 1970s and 1980s have been well documented.
Former FBI agent John Connolly is in prison after being convicted in 2002 of effectively becoming a member of the gang.
Bulger was arrested in Santa Monica, California, where he had been living under an assumed name with his girlfriend, who was sentenced separately to eight years for aiding and abetting him.
Police found some $800,000 in cash and an arsenal of weapons in his modest apartment.