R. Kelly is asking the United States Supreme Court to throw out his convictions for possession of child porn and inducing minors to have sex – claiming his alleged acts occurred decades ago and the charges were therefore barred by the statute of limitations.

Here's the deal ... when R. Kelly was accused in 2020 of possessing child pornography and engaging in sexual acts with underage girls way back in the mid to late-1990s, he argued the statute of limitations had already run its course.

But, prosecutors argued a 2003 law – called the PROTECT Act – made the statute of limitations indefinite for child sex crimes.

Basically, Kelly's attorney, Jennifer Bonjean, argues that because the conduct for which Kelly's now serving time occurred in the '90s but the PROTECT Act wasn't passed until 2003, the Act's expanded statute of limitations doesn't apply to the charges against him.

The PROTECT Act extends the statute of limitations indefinitely for alleged crimes committed AFTER the law went into effect in 2003, but Congress specifically didn't include a clause allowing the law to be applied to alleged conduct committed BEFORE 2003.

You'll recall, Kelly was convicted of six of 13 counts back in 2020 -- three for child pornography and three for inducement counts.

He received a 20-year sentence and was ordered to pay hundreds of thousands of dollars in damages to his alleged victims.