CHICAGO (STMW) — He was caught on camera gleefully joking about the gory details of his plan to abduct, torture, extort and kill a suburban businessman.

But his lawyer says former Chicago cop Steve Mandell should serve less than a dozen years in prison.

The 64-year-old may have been convicted in one of the grisliest and most lurid federal trials in Chicago’s recent history, but he deserves a “glimmer of hope that he will one day be free at an old age,” his attorney Francis Lipuma argues in a court filing ahead of Mandell’s sentencing next month.

Mandell — a former Death Row resident who is suspected of at least five unsolved murders — was found guilty in February of plotting to abduct Riverside businessman Steve Campbell, take him to a purpose-built Northwest Side torture chamber, extort him into turning over property, then kill him and chop him up with a meat cleaver and a buzz-saw on a man-sized butcher’s block.

Hidden FBI cameras inside the torture chamber filmed him joking with accomplice Gary Engel about how he’d turn Campbell’s private parts into a “banana split,” then drain his blood in a giant sink.

Prosecutors previously made it clear they believe Mandell, who has ties to several Outfit figures, should die behind bars. And court-appointed officials who completed a pre-sentence investigation agree that federal sentencing guidelines call for a prison term of life plus five years.

But Mandell continues to deny his guilt. And Lipuma says U.S. District Judge Amy St. Eve should take into account the 14 years Mandell spent in prison after he was sentenced to death for a 1990 murder conviction that was eventually overturned on appeal.

Prosecutorial misconduct led to the collapse of that case, and “the court should consider the fact that Mandell’s constitutional protections were violated” and give him that time back now, Lipuma argues.

Lipuma also wrote that Mandell’s health is failing and that holding the five murders Mandell is suspected of but has not been convicted of is “scurrilous and unfounded.”

Though Mandell was a Chicago cop in the 1970s and he disguised himself as an officer as part of the abduction plot, his police experience didn’t help him in the plot and shouldn’t be held against him, Lipuma wrote.

Lipuma also urged St. Eve not to consider allegations that Mandell plotted from behind bars last year to have North Shore real estate magnate George Michael — the key witness against him — murdered, saying there was no evidence of such a plot.

Mandell, who has a history of burglary convictions and won a landmark $6.5 million civil verdict against the FBI over his 1990 murder case, only to see that verdict also tossed out by a judge, deserves credit for two years he spent in the Army in the 1970s, Lipuma wrote.

“He must be sentenced with the benefit of considering the full measure of the man, including his positive contributions to society and his difficult life story,” the court filing states.

Mandell is due to be sentenced Dec. 11. His accomplice Engel hanged himself in prison soon after their Oct. 2012 arrest.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)