NEW YORK (AP) _ A defense attorney representing his own father, a reputed gangster, in a high-profile mob prosecution must quit the case, a federal judge ruled.

U.S. District Judge Jack Weinstein ruled Thursday that Joseph Corozzo Jr. had a conflict of interest because he once represented a witness in the ongoing racketeering case against the Gambino organized crime family.

The lawyer's father, Joseph "Jo Jo" Corozzo, is accused of being a Gambino consigliere. He was among more than 60 people charged last month in the latest crackdown on a once-mighty crime family already crippled by convictions of high-ranking members.

Corozzo, 41, "is a brilliant attorney probably among the most brilliant in all of New York City," Weinstein said at a hearing in federal court in Brooklyn. "But he cannot represent his father. If Mr. Corozzo wants to attend the trial, he'll attend it as a spectator."

In finding a conflict of interest, Weinstein turned aside a broader argument made by prosecutors, who labeled Corozzo Jr. "house counsel" for the crime group, essentially an associate participating in crime, rather than a mere lawyer.

Federal prosecutors had successfully used a similar argument in the 1990s to disqualify Bruce Cutler, the flamboyant defense lawyer who had won acquittals that gave the late mobster John Gotti his nickname of Teflon Don.

The elder Corozzo has pleaded not guilty to multiple racketeering counts including cocaine trafficking. He sat quietly next to his son at a defense table on Thursday.

The judge appeared to surprise both sides but cutting short the hearing on the prosecutors' arguments and ordering the elder Corozzo to hire a new lawyer because of conflict of interest.

"We're still a little bit stunned," the son said afterward outside court. "We're trying to digest what happened."

The indictment charged the defendants with gangland crimes spanning three decades including the brutal slaying of a court officer and extortion at a failed NASCAR track.

Copyright 2008 The Associated Press.