They say the money was used for vacations, events in Brown's honor and luxury boxes at a Beyoncé concert and an NFL game.
The head of the supposed charity pleaded guilty in March to conspiracy to commit wire fraud. According to First Coast News, she testified against a public official believed to be Brown.
"I'm looking forward to a speedy day in court to vindicate myself," Brown said outside the Jacksonsville courthouse.
Brown will step down from her position as ranking member on the House Veterans Affairs Committee for the duration of the case.
Her district includes Jacksonville and parts of the Orlando area. She's currently running for her 13th term in Congress.
This video includes clips from WPTV, WJXT, C-SPAN, WFTV, WTLV and Congresswoman Corrine Brown and images from A. Duarte / CC BY SA 2.0 and Getty Images. Music provided courtesy of APM Music.