A FEDERAL JUDGE yesterday denied bail to ex-narcotics cop Thomas Liciardello, finding evidence that he was the "de facto leader" of an alleged group of rogue cops, and that he could pose a danger to the community.

After U.S. District Judge Eduardo Robreno ordered him held pending trial on racketeering-conspiracy and robbery charges, Liciardello, 38, looked back toward his wife, Selena, a Philly police officer, and mouthed: "Stay strong."

His wife, who shook as she sat in the gallery next to his mother and stepfather, later cried outside the courtroom.

Liciardello's five co-defendants had been granted bail by Robreno, who ruled that they posed no danger to the community. They will be on house arrest.

The six are accused of robbing suspected drug dealers and others, using violence at times.

Robreno, who heard extensive arguments and testimony at Liciardello's bail hearing on Tuesday, cited evidence in his ruling yesterday that Liciardello was the ringleader. An FBI special agent had testified Tuesday that a majority of the victims said Liciardello was the one who ran the show.

Also, a cooperating witness - Jeffrey Walker, a former narcotics cop who had pleaded guilty in an attempted-robbery case - said that the cops "learned their trade craft from Tommy," the FBI agent testified.

The judge also decided that Liciardello had threatened people and is a danger to the community.

"Liciardello's standard operating procedure" was to "pit drug dealers against other drug dealers," the FBI agent testified.

Assistant U.S. Attorney Anthony Wzorek pointed to a 2007 case in which one cop allegedly dangled a suspected dealer from his 18th-floor City Avenue balcony, prompting the dealer to give up the name of his New York supplier.

When the supplier showed up outside the apartment, the cops arrested him, and Liciardello reportedly told the supplier that the dealer was his "snitch."

The judge decided that Liciardello had done this so that the supplier could retaliate against the "snitch."

The feds also alleged that Liciardello once threatened lawyer Michael Pileggi, who has filed civil suits against cops. The judge said this suggested a tendency by Liciardello "to lash out" at perceived authorities.

The judge pointed to another example concerning a man allegedly held against his will in a hotel for several days. After the man was released, the judge said, Liciardello called the man's wife daily and harassed her until a lawyer told Liciardello to stop.

The wife, in a July 31 interview with the Daily News, said that after her husband was released from the hotel, Liciardello had called her husband daily, harassing him for money. Her husband didn't give Liciardello anything and was depressed and couldn't sleep, the wife had said.