Professors and their social-media controversies

* Steven Salaita - The University of Illinois withdrew a job offer to him in 2014 after his controversial tweets about Israel and its military efforts in Gaza.

* Kaukab Siddique - The associate professor of English at Lincoln University has drawn ire several times for his Facebook posts, most recently in 2015 when he wrote about "dirty Jewish Zionist White Supremacist thugs" and a "homo uprising." The university condemned his remarks but has kept him employed.

* Joyce Karega - Oberlin College dismissed her in November after investigating her anti-Semitic and anti-Israel statements, including an allegation that ISIS is an arm of Israeli and U.S. intelligence agencies.

* Sara Goldrick-Rab - A Temple University professor faced pushback from her former employer, the University of Wisconsin-Madison, for her social media posts, including one in which she called Wisconsin Gov. Scott Walker a "fascist" for wanting to weaken tenure protections.