Prosecutors say Bulger immunity claim 'void'

BOSTON -- A federal prosecutor has told a judge that any immunity agreement reputed gangster James "Whitey" Bulger claims he had with the government would be "void as a matter of law" if it included murder.

Bulger's lawyer argued that only jurors, not a judge, should be allowed to decide if Bulger's immunity claim is valid.

“We need to let the jurors decide if the government gave him immunity and if so, what the scope of the immunity was,” said J.W. Carney, Bulger’s defense attorney.

But the government and victims’ families say Bulger’s word means nothing, and want the judge to investigate.

“He has to prove that. And until they come out with some kind of documents or something like that. And immunity doesn’t fall under the grounds of murder,” said Steve Davis, victim’s brother.

Both sides presented arguments Wednesday to the judge scheduled to preside at Bulger's trial in June.

The former Winter Hill Gang leader is accused of participating in 19 murders.

He claims a federal prosecutor gave him immunity for crimes while he was providing the FBI information on local leaders of his gang's main rivals, the Mafia.

Federal prosecutors asked a judge to decide the issue before trial.

The judge didn't indicate when he would rule.

The Associated Press contributed to this report.