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Before turning to acting, Sirico was reportedly a mob associate of the Colombo crime family serving under Carmine "Junior" Persico and had been arrested twenty-eight times. There is a Sopranos reference to this fact when Paulie says "I lived through the seventies by the skin of my nuts when the Colombos were goin' at it."In 1967, he was sent to prison for robbing a Brooklyn after-hours club, but was released after serving thirteen months. In 1971, he plead guilty to felony weapons possession and was sentenced to an "indeterminate" prison term of up to four years, of which Sirico ended up serving twenty months. In an interview in Cigar Aficionado magazine, Sirico said that during his imprisonment, he was visited by an acting troupe composed of ex-cons, which inspired him to give acting a try. According to a court transcript, at the time of his sentencing, he also had pending charges for drug possession. Sirico appeared in a 1989 documentary about life, The Big Bang by James Toback, in which he discussed his earlier life.

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From Sing Sing To Bada Bing!Tony Sirico's real-life training for his "Sopranos" role

There's a good reason Tony Sirico is so convincing as the menacing Paulie Walnuts on "The Sopranos." Because before becoming an actor, Sirico was a mob-connected thug who dealt speed, packed a loaded Beretta, and was once actually declared a "danger to society" by a New York judge.

In fact, according to court records that read like a David Chase script, Sirico was a feared shakedown artist who preyed on Manhattan nightclubs and who once gave this description of his extortion technique: "You hit them over the head with a baseball bat, and they come around." After a dispute with a disco owner, Sirico once warned, "I'm going to come back here and carve my initials in your forehead. You better learn a lesson, you better show me the respect I deserve." A Bellevue Hospital psychiatric report from that period concluded that Sirico suffered from a "character disorder."

The court records obtained by The Smoking Gun involve Sirico's 1971 conviction for felony weapons possession, a crime for which he was sentenced to a maximum of four years in prison. Sirico ended up serving 20 months in places like Sing Sing, and has, to his credit, avoided trouble since (if you don't count clipping Pussy last season).

We've included the felony affidavit filed against Sirico (who was born Genaro Sirico) and the marvelous transcript from his sentencing, which includes an entertaining narrative offered by prosecutor Gerard Hinckley--it's a must-read for "Sopranos" fans. TSG's favorite section involves a botched police tail of Sirico that ends with the future Mr. Walnuts's auto deftly forcing the unmarked car--Bada Bing!--into a traffic divider.
Tony sirico affidavit
http://www.thesmokinggun.com/file/tony-sirico-felony-affidavit
Sirico sentencing transcript (15 pages)

http://www.thesmokinggun.com/file/sirico-sentencing-transcript