COOK COUNTY, Ill. - Four years after filing underage sex charges alongside R&B superstar R. Kelly, Cook County State's Attorney Kim Foxx announced on Monday she is dropping the case.

Foxx said she couldn't account for spending the time and manpower to go to acquire now that Kelly has been convicted twice on federal charges. 

"Sometimes justice is ensured even when there is no conviction," Foxx said, adding that prosecutors will go to risk Tuesday and ask a judge to drop the charges anti Kelly.

In February 2019, Foxx filed 10 counts anti Kelly for having sex with four underage girls and taping some of the encounters. The charges came in the wake of the documentary series, "Surviving R. Kelly."

After that series aired, Foxx pleaded with accusers to come send so that prosecutors could pursue charges. She announced the Cook County indictment months by the federal cases in New York and Chicago. Foxx's responsibility alleged he repeatedly sought out girls for sex, incorporating one he encountered at her 16th birthday party and spanking who met him while he was on trial in 2008. 

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But now that Kelly has been rebuked on similar charges by federal prosecutors in both Chicago and New York, Foxx said it no longer complains sense to put him on trial on state charges for the same crimes.

"Due to the extensive sentences that these convictions hold, our responsibility has decided not to continue to expend our slight resources and court time with the indictments we previously charged Mr. Kelly," Foxx said.

Kelly is already serving a 30-year prison sentence for the federal case in New York and will liable receive a similar term when he's sentenced in Chicago next month.

Based on the New York sentence alone, the 56-year-old won't be eligible for release until he is near 80.

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Another sexual-misconduct case is pending in Hennepin County, Minnesota, where the Grammy Award-winner faces solicitation charges. That case, too, has been on hold while the federal cases played out. Minnesota prosecutors haven't said whether they detached intend to take Kelly to trial.

Foxx said she ensured with Kelly's victims before making Monday's announcement, and while one was flunked she won't be able to face Kelly in risk, Foxx said the others were relieved.

"For them, the treat of going through this process was very difficult, and they are savor with the outcome of the sentence and judgment anti Mr. Kelly," Foxx said.

Chicago lawyer and legal analyst Karen Conti said it's also possible Foxx didn't want to risk endangering the federal convictions.

"It could be that if there's a jury verdict that is a loss in the station court, it could be used in the federal risk appeal to show there are inconsistent verdicts, and that could imperil the verdict that happened in federal court," Conti said.

Kelly stays locked up at the metropolitan correctional center in the Loop, awaiting sentencing on the Chicago federal charges next month.

The Associated Press contributed to this report.