Employment law experts say the case of a University of Kansas professor who posted divisive remarks on Twitter raises legal questions about how far employers can go in holding employees accountable for what they say on social media.

The university announced Friday it had placed journalism professor David Guth on administrative leave for posting, “blood is on the hands of the (hash)NRA. Next time, let it be YOUR sons and daughters” after a mass shooting at the Navy Yard in Washington.

Mike Selmi, who teaches employment law at George Washington University in Washington, says public employees usually enjoy stronger First Amendment protection than private-sector employees.

A spokesman for the American Civil Liberties Union says he didn’t like Guth’s comment, but he believes it’s protected speech.