A group of Christian students at North Carolina State University filed a federal lawsuit against school officials Tuesday over the university’s policy requiring a permit for any kind of student speech or communication that takes place on campus.

The lawsuit claims that public universities can’t require permits for speech on campus and can’t enforce speech rules selectively. It asks the court to invalidate the university’s speech permit policy as being unconstitutional.

Last September, according to the lawsuit, school officials told members of Grace Christian Life that they needed a permit to speak with other students about religion, or to invite them to the group’s events, in the Talley Student Union.

Members of the group obtained a permit and set up a table in the union in January. They say they were told that they could speak with other students from behind the table, and that when some of them left the table, a member of the Student Involvement Office approached them to tell them that they had to stay behind the table.

The lawsuit states that the university does not place the same restriction on other students and student groups, and that Christian Life members have seen other groups speaking freely with students and handing out literature, in full view of university officials.

Attorneys from the Alliance Defending Freedom, a conservative Christian nonprofit that defends religious speech through “strategy, funding, training and litigation,” are representing the registered student organization.

“Public universities are supposed to be the marketplace of ideas, not places where students need a permit just to exercise their constitutionally protected freedoms,” said ADF Senior Counsel Tyson Langhofer. “The only permit needed to engage in free speech is the First Amendment.”

In a statement from the university’s news service, N.C. State called the lawsuit “frivolous and without merit:”

N.C. State University administers the distribution of materials on campus for commercial or non-commercial use through a permitting process. The university allows individuals or groups to distribute materials on campus after obtaining a permit. The permitting process is applied consistently to all groups distributing materials.

N.C. State issues a permit for all such activities subject to constitutionally appropriate and reasonable time, place, or manner limits, without regard to the content or the viewpoint of the information being distributed.

N.C. State’s permitting process is constitutional, does not infringe on First Amendment rights, and is in compliance with applicable state and federal law. In fact, hundreds upon hundreds of individuals and groups have used this process each year to distribute information regarding topics ranging from faith to politics to health and any number of other interests.

N.C. State believes this lawsuit is both frivolous and without merit. NC State steadfastly remains willing to work with all individuals and organizations to educate them about the process and help them obtain a permit for distributing information and/or soliciting on campus.

Read the lawsuit below.