The attorney for Steven Mandell — the man convicted in February of a 2012 plot to kidnap, extort and kill a Riverside businessman — has requested a federal judge acquit Mandell and give him a new trial.

The request was detailed in an Oct. 10 filing that sneered at federal prosecutors’ and the FBI’s conduct in collecting evidence and presenting it at trial.

Francis C. Lipuma, who was appointed Mandell’s attorney in May after Mandell claimed his former counsel was incompetent, pointedly slammed the government’s star witness, Northwest Side real estate mogul George Michael, as unreliable and a liar.

“George Michael’s testimony lacked any measure of credibility, and the evidentiary value of the documentary and physical evidence was lacking,” Lipuma wrote in his filing. “Clearly, the government should not be permitted to take away Mandell’s liberty based on the record before the court.”

Lipuma also harshly criticized the conduct of FBI Agent Richard Tipton and the FBI, claiming they improperly withheld information from an affidavit submitted to Judge James Holderman (at the time the chief judge of the U.S. District Court for Northern Illinois) in order to have Holderman approve a request to secretly record activities inside a building on Chicago’s Northwest Side.

That building became known, infamously, during the trial as “Club Med,” where Mandell, 63, and an associate named Gary Engel planned to carry out their scheme to torture Riverside businessman Steven Campbell in order to obtain cash and deeds to properties and then kill and dismember him.

Video and audio recordings from Club Med, which were made on Oct. 24 and 25, 2012, were played at trial and gave jurors grisly visual and audio evidence of the duo’s lurid plot.

Tipton’s affidavit, which was dated Oct. 18, was filed in support of the government’s request to place a secret video camera inside Club Med. The FBI stated it needed judicial OK for the secret surveillance in order to “prove the subject offenses and fully identify Mandell’s co-conspirator.”

According to Lipuma, the FBI knew Engel was Mandell’s co-conspirator as early as September and that Tipton acknowledged in a subsequent affidavit that the FBI had that information by at least Oct. 2.

Those omissions, according to Lipuma, “were essential to the establishment of probable cause [and] suppression of all communications and all evidence derived from the seizures was required.”

Mandell has a track record of wriggling out of lengthy prison sentences — even the death sentence.

Both Mandell and Engel were sentenced to life in prison in Missouri in 1992 for a kidnapping and extortion plot, allegedly carried out in 1984. While serving time for that conviction, Mandell was fingered as the killer of a former business partner in 1990. He was sentenced to death for that offense.

But Mandell appealed the murder conviction to the Illinois Supreme Court, claiming that the government had improperly admitted a statement made by Mandell’s alleged victim prior to his death. The court overturned the conviction and the case was never re-tried.

Similarly, a federal appeals court overturned the kidnapping convictions of Mandell and Engel, ruling the FBI improperly gathered evidence in that case, which was also never re-tried.

Mandell later sued the FBI and won a $6.5 million judgment against the agency. But the judgment was later vacated and Mandell never collected a cent.

Prosecutors are slated to file a reply to Lipuma’s arguments on Oct. 27. Mandell is scheduled to be sentenced on Dec. 11.