BOSTON (AP) — James “Whitey” Bulger, a former mob boss who eluded prosecution for 16 years, pleaded not guilty to federal racketeering charges that accuses him of participating in 19 murders.

The plea in Boston federal court Wednesday by Bulger, a former FBI informant, came 16 years after he fled following a federal agent’s warning on a separate, pending indictment.

Bulger escaped prosecution until he was captured last month in California.

The arraignment comes after Bulger’s attorney asked a judge to appoint his law partner to help him defend the 81-year-old Bulger.

J.W. Carney Jr. was appointed last week after a magistrate judge found Bulger to be indigent. Carney is asking that attorney Janice Bassil be appointed to help him with a case he says has a “host of complex legal issues.”

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