HOUSTON—A former Texas Southern University student testified that he was paid $5,000 by the FBI to tape university officials in the midst of a corruption investigation.

Oliver Brown and two other former students filed a civil lawsuit against TSU officials for allegedly thwarting their First Amendment rights by disciplining them for their anti-corruption speech. The lawsuit alleges they were retaliated against for exposing corruption at the university.

Known as the “TSU Three,” Brown, William Hudson and Justin Jordan, helped bring to light a spending scandal that led to plea bargains with ex-school President Priscilla Slade, who promised to repay $130,000, and former CFO Quintin Wiggins, who was sentenced to 10 years in prison.

“We stood up for the taxpayers’ right to know how their money was spent,” Brown said in a story Tuesday in the Houston Chronicle’s online edition. He held a news conference at lunch on Monday outside the courthouse.

Brown said he received a lump sum after working as a federal informant for 18 months, beginning in 2005.

Peter Plotts, assistant Texas attorney general representing TSU officials, said the focus of the case is not on protected speech but that the former students were disciplined for separate threatening or abusive speech.

“The university is obliged not only to encourage speech and the free flow of ideas but also to teach civility,” Plotts said. He said some of the students shouted at officials, called them names and made threats.

The trio is asking the jury to award each of them $1,000 a week for three years, said defense attorney Patrick Gilpin.