CHICAGO — Once known as a tireless bloodhound who tracked down fugitive gang leaders, deputy U.S. marshal John T. Ambrose now faces charges alleging he betrayed his oath and leaked secrets to the mob.
Ambrose, 50, is due to go on trial Monday for allegedly telling organized crime figures seven years ago that a so-called made member of the Chicago mob had switched sides and was providing detailed information to federal prosecutors. Ambrose denies he ever broke the law in handling secret information.
"The feds are guaranteed to see this as the worst sort of treachery," says mob expert John Binder, author of "The Chicago Outfit." ''I don't think I'm overblowing it. They're going to see him the way the military sees a Benedict Arnold."
If convicted, Ambrose could face years behind bars.
U.S. District Judge John F. Grady has ordered extraordinary security including screens in the courtroom to conceal the faces of key witnesses from spectators. Inspectors in the government's supersecret Witness Security Program operated by the U.S. Marshal's Service will testify behind the screens and use pseudonyms.
The idea is to prevent anyone from identifying the inspectors, whose job it is to guard heavily protected witnesses from mob assassins, terrorists or others who might want to silence them.
Ambrose defense attorney Francis C. Lipuma objected to the screens and testimony under false names.
"This is going to sensationalize the trial," Lipuma said at a recent hearing.
Ambrose is accused of leaking information to the mob about an admitted former hit man, Nicholas Calabrese, who was the government's star witness at the landmark 2007 "Family Secrets" trial that targeted top members of the Chicago mob.
As a trusted federal lawman, Ambrose was assigned to guard Calabrese on two occasions when witness security officials lodged him at "safe sites" in Chicago for questioning by prosecutors.
Ambrose is charged with stealing information from a Witness Security Program file on Calabrese and passing it to a go-between believing it would go to reputed mob boss John "No Nose" DiFronzo.
He's accused of leaking information only about the progress of the investigation — nothing about the whereabouts of the closely guarded witness — but prosecutors say it still could have put Calabrese in jeopardy.
"Anyone who has even occasionally read a Chicago newspaper in the last 20 years knows what the potential consequences of testifying against the so-called Mafia are," the judge told attorneys at a hearing last week.
The "Family Secrets" trial was Chicago's biggest mob trial in years. Three of the top members of the mob including Calabrese's brother, Frank, were sentenced to life in prison and two other men received long terms behind bars.
Nicholas Calabrese admitted he was involved in the murders of Tony "The Ant" Spilotro and his brother, Michael. Tony Spilotro was the model for the character played by Joe Pesci in the movie "Casino."
Nicholas Calabrese also said one of the Family Secrets defendants, reputed mob boss James Marcello, was among those present when the Spilotro brothers were strangled.
Calabrese agreed to cooperate in the Family Secrets investigation in 2002 after a bloody glove yielded DNA evidence placing him at a murder scene.
Ambrose was charged after federal agents bugged the visitors room at the federal prison in Milan, Mich.
James Marcello was an inmate there and was visited by his brother, Michael Marcello, a video game company operator who eventually pleaded guilty to racketeering.
Authorities overheard the Marcello brothers discussing a mole they had inside federal law enforcement who was providing security for Calabrese. They called him "the babysitter."
The government says agents narrowed the possible suspects to Ambrose when one of the Marcellos said "the babysitter" was the son of a Chicago policeman who went to prison decades ago as a member of the Marquette 10 — officers convicted of shaking down drug dealers.
Prosecutors also say Ambrose's fingerprint was later found on the file.