(BOSTON) -- Convicted assassin John Martorano confessed to killing 20 people -- including innocent bystanders -- but served just 12 years in prison in exchange for his testimony against accused Boston mob boss James "Whitey" Bulger.
On Monday, more than a decade after Martorano cut that deal with the government, he will face his one-time friend in court.
Martorano, 72, has been a free man since 2007 and Bulger's defense attorney J.W. Carney tried to delay the trial by arguing that the hitman has continued a life of crime, a claim that was denied by prosecutors and dismissed by a federal judge.
Still, Carney insists that Martorano -- and other government witnesses expected to testify against Bulger -- are not credible because they pointed fingers at one another to avoid lengthy prison sentences. Bulger's sidekick, Kevin Weeks, and right-hand-man, Stephen "The Rifleman" Flemmi, are also on the witness list.
Carney had especially harsh words for Martorano calling him "criminal psychopath."
"He would kill people almost randomly. He would kill people as easily as we would order a cup of coffee... The federal government was so desperate to have John Martorano testify ... they basically put their hands up in the air and said take anything you want," Carney said.
Martorano will testify after cross-examination of Boston bookmaker Dick O'Brien, 84, who was one of two bookies who testified that they paid "rent" to Bulger to stay in business. He recounted Bulger telling one bookmaking agent who got out of line that he liked to "kill a**holes like him." James Katz, 73, also testified that people who didn't pay Bulger could "wind up in the hospital."
Bulger, 83, is charged with a 32-count indictment that includes accusations that he committed or ordered 19 murders, including the killings of two women who were romantically involved with his underlings. Bulger's trial comes 18 years after an indictment naming him was unsealed, but he had been tipped off by rogue FBI agent John Connolly and disappeared.
He was arrested in June 2011 at a Santa Monica apartment complex where Bulger and his longtime companion Catherine Greig lived for 16 years as Charlie and Carol Gasko, strolling the California coastline and shopping on the Third Avenue Promenade.
Carney accused the FBI of "pretending to look for him" during opening arguments last week. The government called those accusations absurd.
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