What the First Amendment doesn’t protect when it comes to professors

American colleges and universities are increasingly firing or punishing professors and other employees for what they say, whether it’s on social media or in the classroom.

After the Sept. 10, 2025, killing of conservative activist Charlie Kirk, several universities, including Iowa State University, Clemson University, Ball State University and others, fired or suspended employees for making negative online comments about Kirk.

Some of these dismissed professors compared Kirk to a Nazi, described his views as hateful, or said there was no reason to be sorry about his death.

Some professors are now suing their employers for taking disciplinary action against them, claiming they are violating their First Amendment rights.

In one case, the University of South Dakota fired Phillip Michael Cook, a tenured art professor, after he posted on Facebook in September that Kirk was a “hate spreading Nazi.” Cook, who took down his post within a few hours and apologized for it, then sued the school, saying it was violating his First Amendment rights.

A federal judge stated in a Sept. 23 preliminary order that the First Amendment likely protected what Cook posted. The judge ordered the University of South Dakota to reinstate Cook, and the university announced on Oct. 4 that it would reverse Cook’s firing.

Cook’s lawsuit, as well as other lawsuits filed by dismissed professors, is testing how much legal authority colleges have over their employees’ speech – both when they are on the job and when they are not.

For decades, American colleges and universities have traditionally encouraged free speech and open debate as a core part of their academic mission.

As scholars who study college free speech and academic freedom, we recognize that these events raise an important question: When, if ever, can a college legally discipline an employee for what they say?

Limits of public employees’ speech rights

The First Amendment limits the government’s power to censor people’s free speech. People in the United States can, for instance, join protests, criticize the government and say things that others find offensive.

But the First Amendment only applies to the government – which includes public colleges and universities – and not private institutions or companies, including private colleges and universities.

This means private colleges typically have wide authority to discipline employees for their speech.

In contrast, public colleges are considered part of the government. The First Amendment limits the legal authority they have over their employees’ speech. This is especially true when an employee is speaking as a private…