John Oliver turned his attention to for-profit policing on Sunday's Last Week Tonight, specifically the municipalities that target low-income black residents with fines and court fees to balance the books.

John OliverJohn Oliver went after for-profit policing in Sunday's Last Week Tonight

"No one is saying that people who break the law should not be punished," Oliver began. "Not only should municipalities not be balancing their books on the backs of some of their most vulnerable citizens, but we cannot have a system where committing a minor violation can end up putting you in - and I'm going to use a legal term of art here - the f*ck barrel."

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Clearly Oliver's views chimed with Twitter users and #shutdownthef*ckbarrel began trending on the micro blogging site.

To support his argument, Oliver cited the story of Harriet Cleveland, a woman who went to jail in Alabama after racking up a series of traffic violations.

"I had my grandbaby with me, and I was setting up, giving him breakfast that morning, and I heard a knock on the door, and I saw a police officer at my door," she told the Southern Poverty Law Center. "In the back of my mind, it wasn't for me, because I didn't figure they'd come get you for tickets. I was escorted to jail."

In various cities in the U.S, failing pay a parking ticket can lead to license suspensions and even jail. Private for-profit companies like Judicial Correction Services handle debts for local governments and aim to rack up as much cash as possible. 

Cleveland spent 10 days in prison before being released. 

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