Students who were interrogated after holding a free speech event on campus filed a lawsuit Tuesday against the University of South Carolina for violating their First Amendment rights.

Student Ross Abbott and the campus chapters of the Young Americans for Liberty and College Libertarians filed the lawsuit, which challenges a number of the university’s policies—including its free speech zone and the requirement that students register in advance before they can exercise their First Amendment rights.

The lawsuit, sponsored by the Foundation for Individual Rights in Education (FIRE), also challenges USC’s Student Non-Discrimination and Non-Harassment Policy, claiming it is a vague and overbroad restriction that prohibits "unwelcome" speech and "suggestive or insulting gestures or sounds."

"I held an educational event for students to learn about their free speech rights. Apparently it was my school’s administrators that needed the lesson," said Abbott in a prepared release. "Now, with FIRE’s help, we’re going to give it to them."

The student’s free speech event, held last November, featured information and posters depicting 11 instances of campus censorship across the country.

The examples included a case in California in which a student was banned from handing out copies of the U.S. Constitution on Constitution Day, a faculty blog being censored by Chicago State University, and George Washington University suspending a Jewish student for placing a souvenir Hindu swastika on his residence hall’s bulletin board.

Abbott was summoned for questioning to the Office of Equal Opportunity Programs despite the fact that Abbott and the groups obtained prior approval from the university after some students complained that the subject matter offended them and that they felt "triggered"

"The University of South Carolina is so intolerant of free speech that students can’t even talk about free speech," said Catherine Sevcenko, FIRE’s director of litigation, in a prepared statement.

One of the defendants in the lawsuit, assistant director of the Office of Equal Opportunity Programs Carl Wells, was unaware of the lawsuit when contacted by the Washington Free Beacon. "Thank you for the information. I have no comment," he said.

Wells, the lawsuit claims, interrogated Abbott and YAL president Michael Kriete for 45 minutes about each poster.

Abbott gave Wells a letter requesting his disciplinary record be expunged, the university clarify its policies regarding controversial speech, and adopt the Chicago Principles.

Wells notified Abbott two weeks later the matter was being dropped but did not address the other issues.

"Even if University of South Carolina students play by the unconstitutional rules and seek permission to exercise their rights, they still risk punishment," said Sevcenko. "No one should have to explain their speech to a government bureaucrat under threat of punishment, especially on a college campus, but that is exactly what USC made Ross do."