Kelly is charged in New York with coercing women and girls into sexual activity as far back as 20 years ago, in the U.S. and overseas. The accusers were required to call Kelly "Daddy" and were told to keep their heads down and not look at other men, according to the indictment.
In Chicago, Kelly faces 13 charges that focus on producing and receiving child pornography and inducing minors to engage in sexual activity. The indictment also describes an alleged conspiracy to pay hundreds of thousands of dollars to people to cover up evidence of sexual contact with minors. The indictment says Kelly directed people to take polygraph tests to confirm that they returned incriminating videos.
"He's in for the fight of his life," said Renato Mariotti, a former federal prosecutor in Chicago. "You have to assume he's going to vigorously contest these charges. But having a multi-front war gives the advantage to prosecutors."
WHAT'S THE REACTION IN KELLY'S CAMP?
Attorney Steve Greenberg said Kelly was aware of the investigation and the charges "were not a surprise."
"He and his lawyers look forward to his day in court, to the truth coming out and to his vindication from what has been an unprecedented assault by others for their own personal gain," Greenberg said.
Kelly, 52, appeared in federal court in Chicago and will remain in custody until at least Tuesday.
It's been a stormy year for Kelly: Lifetime network in January began airing the documentary "Surviving R. Kelly." The series looked at the singer's history and allegations that he has sexually abused women and teen girls. Kelly has denied any wrongdoing.
WHY ARE THE FEDS INVOLVED?
Kelly's alleged crimes trigger many federal laws, especially child pornography and illegal activities that cross state lines. The penalties can be severe: Some child pornography crimes carry mandatory minimum prison sentences of five years or more.
"State prosecutors are overburdened," Mariotti said. "The feds have more freedom to put additional resources into a case like this. ... A lot of work went into these indictments and it shows."
He believes Kelly's celebrity status got the attention of authorities, too.
"His apprehension and potential conviction could have significant deterrent impact," Mariotti said. "This is somebody they're making movies about. It can send an important signal to victims that they can come forward because justice can be done. It also sends a signal to other perpetrators."
WHICH CASE GOES FIRST?
No one knows yet. The state charges against Kelly were filed months ago and are pending. Cook County State's Attorney Kim Foxx said the federal charges demonstrate the "collaborative efforts of our criminal justice system."
Mariotti said there is no rule about which case is called first, although the defense might have a preference. There's also a wild card: Two former Kelly employees were indicted with him. It's possible they could make a deal with the government and cooperate with investigators.
Attorney Gloria Allred said she represents three women who are part of the New York case and other potential witnesses. She praised their "courage" and said Kelly "no longer has the power to intimidate" them.
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