CHICAGO — Federal prosecutors failed to meet their burden when they presented their case against R. Kelly, a case that was built almost entirely on the word of serial liars, Kelly’s attorney said Tuesday during her closing argument.

“I ask that you find Mr. Kelly not guilty of all the counts,” Jennifer Bonjean said at the conclusion of her 90-minute argument to jurors.

“I ask you, more importantly, that you go back there, please, and you remember each count counts, and you do your job and you take as long as you need because our system requires it,” she continued. “Mr. Kelly deserves it no matter what you think of him.”

Bonjean described Kelly, 55, as a victim of opportunistic “lowlifes” who, for years, exploited and extorted the singer for hundreds of thousands of dollars.

After 18 days of jury selection, witness testimony, objections and arguments, the jurors in the case are set to start deliberations Tuesday afternoon on each of the 13 counts brought against Kelly and his two co-defendants. Jurors started deliberations shortly after 1 p.m.

During her rebuttal argument, Assistant U.S. Attorney Jeannice Appenteng accused Derrel McDavid — Kelly’s former business manager and one of his co-defendants — of lying when he testified in his defense earlier in the trial. Elizabeth Pozolo, another of the federal prosecutors, made the same assertion a day earlier.

McDavid repeatedly testified that he did not believe the early allegations against Kelly because Kelly’s legal team assured him of the singer’s innocence. Several key figures in the defenses’ arguments — Kelly’s former attorneys Edward Genson, Gerald Margolis and private investigator John “Jack” Palladino — died before the ongoing trial began.

“During any key event where he would have knowledge of Kelly’s sexual abuse of Jane, [McDavid] is conveniently absent,” Appenteng said.

A federal grand jury in Chicago indicted Kelly on 13 counts in July 2019, accusing him of producing and receiving child pornography, while also enticing minors to engage in illegal sexual activity.

McDavid and Milton “June” Brown, a former assistant to Kelly, are charged with one count of conspiracy to receive child pornography. McDavid also faces two counts of receiving child pornography and one count of conspiracy to obstruct justice related to Kelly’s 2008 child pornography trial in Cook County.

Prosecutors allege Kelly and those in his inner circle paid out hundreds of thousands of dollars over the years in an effort to track down video tapes that Kelly made that allegedly show him engaging in sexual activity with underage victims.

Earlier this year, Kelly was sentenced to 30 years in prison after a jury in Brooklyn found him guilty of racketeering and sex trafficking. Kelly also faces a criminal case in Cook County and another in Minnesota.