Four men convicted in Chicago's biggest mob trial in years are fighting to avoid life sentences for a racketeering conspiracy involving extortion, loan sharking and murder.

A fifth defendant, Anthony Doyle, 62, a retired Chicago policeman, was also convicted of racketeering conspiracy, but he is not accused of direct involvement in any of the 18 killings listed in the indictment and is not facing the possibility of a life sentence.

A jury found the men guilty Monday in federal court after deliberating for less than 20 hours. The ruling came after 10 weeks of testimony describing how victims were bludgeoned, strangled and shot by Chicago mobsters.

The trial focused on killings that were among the mob's darkest secrets — including that of Tony "The Ant" Spilotro, the Chicago mob's longtime man in Las Vegas, who inspired the Joe Pesci character in the movie "Casino."

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Most of those killed were either federal witnesses in organized crime investigations or people the mobsters feared would become witnesses.

Jurors must decide whether any of the four defendants should go to federal prison for life.

Convicted of racketeering conspiracy were alleged mob boss James Marcello, 65; alleged mob capo Joseph "Joey the Clown" Lombardo, 78; convicted loan shark Frank Calabrese Sr., 70, and convicted jewel thief Paul Schiro, 70.

Marcello was also convicted of gambling charges and obstruction of justice. Calabrese was found guilty of bookmaking and extortion. Lombardo was convicted of obstruction of justice.

Each of the men is accused of direct involvement in at least one murder.

If any defendant is determined to be responsible for a murder, jurors must decide whether the killing "was accompanied by exceptionally brutal and heinous behavior indicative of wanton cruelty." Federal law calls for a life prison sentence in such cases.

Prosecutors and defense attorneys will get to address the jury before it begins what amounts to a second round of deliberations.

It may also be left to jurors to decide whether the defendants should be forced to pay a forfeiture. Federal prosecutors want the defendants to forfeit $10 million, total.

The defendants watched pokerfaced as the clerk read the verdicts in U.S. District Judge James B. Zagel's courtroom.

Doyle, the only defendant allowed to remain free on bond during the trial, was taken into custody on Zagel's orders minutes after the verdict. The judge set a Wednesday hearing on Doyle's claim that he should be allowed to remain free on bond because of his wife's frail health.

From the start, prosecutors asked the jurors to forget what they learned from "The Godfather" movies, but the testimony that followed was fit for a Hollywood script.

Witnesses described former friends being blindly lured to their deaths, the relentless squeezing of a mob bookie and a pizza restaurant operator for thousands of dollars in "street tax," and clandestine rituals where "made guys" had their fingers cut and were required to take an oath while holding burning religious pictures.

The government's star witness was Nicholas Calabrese, an admitted hit man who cooperated with prosecutors in the hopes of avoiding a death sentence. He said his brother, Frank Calabrese, ran a loan sharking business and specialized in strangling victims with a rope, then cutting their throats to make sure they were dead.

Frank Calabrese admitted in court that he associated with mobsters, but denied being one himself.

Yet his brother described a 1983 killing in which the two blasted away on a Cicero street, killing two.

"In my mind, I knew I had to do this because if I didn't, my brother would have flattened me," Nicholas Calabrese testified. "I would have been left there."

Frank Calabrese's own son helped the FBI tape conversations with his father while both were serving time for a loan-sharking conviction. In court, the son translated for jurors: When his father tells him to "keep 10 boxes of Spam ham, 'He's telling me to keep $1,000 a month for myself,"' he said.

In Spilotro's case, witnesses testified that mob higher-ups were enraged at him for making side deals with the potential to attract federal investigators. It seemed he was also having a love affair with another mobster's wife.

Frank Calebrese's attorney, Joseph Lopez, had urged jurors not to trust his client's brother.

"He would shoot you in the head over cold ravioli," Lopez declared.

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