Washington (CNN) Cory Booker, who is running for the Democratic presidential nomination, channeled Democrats' fury at the unexpectedly light sentence for Paul Manafort, which the senator from New Jersey learned of the day he released a new sentencing plan and as he was just about to appear on "The Late Show with Stephen Colbert."

Manafort's sentence was less than a quarter of what prosecutors had recommended, a lenience that Booker said probably wouldn't be offered to a drug offender or a minority offender. There's plenty of data to back Booker up.

"This news came out about Paul Manafort, and I'm really ticked off about this," said an agitated Booker, who then gave an informed speech on inequality.

"One of my friends says we have a criminal justice system that treats you better if you're rich and guilty than if you're poor and innocent," he said on Colbert's show. "And there are people from neighborhoods like mine in America" -- Booker lives in an inner city, Newark -- "who get convictions for doing things that two of the last three presidents admitted to doing": smoking marijuana.

Senator @CoryBooker stops by #LSSC tomorrow night, but we've got an early look at his reaction to the #Manafort sentencing. pic.twitter.com/00H8RUaVfY — The Late Show (@colbertlateshow) March 8, 2019

He went on: "We are a nation right now that churns into our criminal justice system the most vulnerable people. You can tell a lot about a country by who they incarcerate. So in Russia, they incarcerate political opposition. In Turkey, they're actually incarcerating the media -- be careful when you travel there, sir. But in our country, we prey upon the most vulnerable citizens in our nation. Poor folks. Mentally ill folks. Addicted folks. And overwhelmingly black and brown folks."

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