BOSTON (AP) -- Reputed Boston gangster James "Whitey" Bulger kept his end of a bargain to cooperate with the government in exchange for immunity from federal prosecution, and now the government should keep theirs, Bulger's attorneys say.
Bulger should be able to present evidence about the alleged deal during his trial over his role in 19 killings, his attorneys argued in papers filed Monday in federal court in Boston.
Prosecutors said in their response that Bulger's claim is "absurd."
Bulger's lawyers said in their brief that Bulger has never claimed -- as prosecutors have said -- that he had "a license to kill," only that he can't be prosecuted for federal crimes committed while the deal was in effect. They concede he could be prosecuted by state authorities.
"The defendant did not possess a license to kill but rather an agreement with the Department of Justice," they wrote. "He seeks only that the DOJ honor its promise to refrain from prosecution."
Prosecutors responded in their filing Tuesday that Bulger's claim about an immunity deal is baseless, and there is nothing to support it.
"Unfortunately for the defendant, no document exists to support his extraordinary claim that he has immunity from prosecution for his lifelong crime spree that ranged from extortion to narcotics distribution to murder," prosecutors said in the filing, adding that Bulger has refused to provide any evidence of it.
The 83-year-old Bulger, who is allegedly a former FBI informant, is accused of committing his crimes in the 1970s and 1980s, when he ran the Winter Hill Gang. He fled Boston in 1994 and was captured in California in 2011.
Bulger attorneys J.W. Carney Jr. and Henry Brennan argued that Bulger's deal with a prosecutor, the late Jeremiah O'Sullivan, was valid until O'Sullivan left the U.S. attorney's office in 1989.
"The Department of Justice is therefore barred from prosecuting the defendant for any crimes that occurred prior to 1989," they wrote.
The defense argued that the court can't invalidate the agreement because it has no legal basis to review a federal prosecutor's decision not to prosecute someone.
The defense also said Bulger performed "his duty" throughout the deal but weren't specific about what that duty was and have said Bulger will testify he was never an informant.
In their brief, prosecutors said that claim is "extraordinary" and "incoherent" and Bulger "continues to dodge his obligation to supply any information to the court regarding his immunity claim rather than a vague allegation" about O'Sullivan.
In other court documents, prosecutors have said 700 pages of FBI reports prove Bulger was an informant. And they've called Bulger's argument that he was free to commit crimes, even though he wasn't an informant, "strange and unsubstantiated."
In their filing Tuesday, prosecutors said "the defendant prefers to twist himself into a pretzel rather than admit the truth, i.e., that he was an FBI informant."
In a separate filing, Bulger's attorneys moved to have a previous judge's rulings on the immunity claim vacated and reconsidered by "a judge of unquestioned neutrality."
The previous judge, U.S. District Judge Richard Stearns, was removed from the case because he worked in the U.S. attorney's office when Bulger says O'Sullivan gave him the immunity deal.
Stearns had barred Bulger from claiming he received immunity for future crimes but requested more information about the alleged deal clearing him for past crimes.
Prosecutors responded that there's nothing to justify reconsideration of Stearns' ruling by the new judge.
In a separate filing Monday, prosecutors said it would be "unnecessary and ill-advised" to force them to turn over an informant's name, as Bulger has requested.
Bulger's lawyers argue the informant could help discredit a key witness against Bulger, his longtime associate Kevin Weeks, by contradicting Weeks' story that he, Bulger and two other men legitimately won a $14.3 million lottery prize that they split. The informant told an FBI agent the prize was part of a money-laundering scheme.
But prosecutors say the informant's identity is irrelevant to Bulger's case because Bulger isn't charged with any crime related to the winning lottery ticket. They also argue disclosing the name would endanger the informant.
"(Bulger) is charged with killing a number of government informants and, if freed, would undoubtedly seek revenge on anyone who assisted the government in making a case against him," prosecutors wrote.
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