R. Kelly's defense team seeks acquittal or new trial following federal child pornography conviction

CHICAGO (CBS) -- Attorneys for disgraced singer R. Kelly filed two motions in federal court on Tuesday, asking a judge to either grant him a new trial, or throw out his September conviction on child pornography and other sex crime charges.

The motions are routine steps following criminal convictions, and are rarely granted, but lay out arguments that Kelly defense attorney Jennifer Bonjean will likely include in an appeal to the 7th Circuit U.S. Court of Appeals.

In September, a federal jury convicted R. Kelly convicted of six counts in federal trial in Chicago, accusing him of sexually abusing his 14-year-old goddaughter "Jane" and other girls on video. The same jury acquitted him of seven other charges, including obstruction of justice, and conspiracy to receive child pornography, accusing him and two associates of rigging his 2008 child pornography trial in Cook County. His two associates, Derrel McDavid and Milton Brown, were acquitted of related charges.

In the motion seeking a new trial for Kelly, Bonjean claimed a key government expert witness misled the jury about how much he was paid for his work on the case.

Dr. Darrel Turner, a licensed clinical and forensic psychologist, testified about how sex offenders "groom" child victims to keep sexual abuse secret.

Turner testified that federal prosecutors paid him $250 per hour for his work, but Bonjean's motion claimed his contract reflected an hourly rate of $450 per hour. Turner also testified he worked on the case for two hours before testifying, but Bonjean wrote that an invoice showed he charged the feds for 6.5 hours of trial preparation.

Bonjean argued prosecutors knew Turner's testimony regarding how much he was paid for his work was false, and didn't correct it. She claimed that entitles Kelly to a new trial.

"Had the jurors known that Dr. Turner actively misled them, the jurors would likely have rejected his testimony outright," Bonjean wrote.

In her bid to have Kelly's conviction tossed out entirely, Bonjean argued federal prosecutors failed to prove Kelly knowingly took steps to "persuade, induce, entice or coerce" Jane or the other victims to engage in illegal sexual activity.

Bonjean also argued prosecutors' evidence failed to show Kelly engaged in sexually explicit conduct with Jane for the "purpose" of child pornography, and that prosecutors failed to prove that any of the sex tapes shown to jurors ever crossed state lines.

Federal prosecutors have until Dec. 6 to respond to Bonjean's motions.

Kelly' sentencing is scheduled for Feb. 23. He is already facing a 30-year prison sentence following a racketeering conviction last year in New York, and faces decades more behind bars for the conviction in his Chicago case.

Meantime, Cook County prosecutors earlier this week sought more time to decide whether to proceed with four indictments accusing Kelly of sexually abusing or assaulting four victims, three of whom were girls at the time.