Updated: Mar 15, 2020
A recent AAUP report, Campus Free-Speech Legislation: History, Progress, and Problems, documents and contextualizes how The Goldwater Institute, a conservative think tank, led the effort for states to adopt campus free-speech bills.
NCA also reported on states passing campus free speech bills here.
"This Renowned German Professor Was Headed to U-Va. to Teach About the Rise of Far-Right Extremism. The State Department Held Up His Visa." By Moriah Balingit Washington Post
"The Church, Universities and Poland" By John Morgan (for Times Higher Education) Inside Higher Ed
"When a 'Threat' Derails a Career" By Colleen Flaherty Inside Higher Ed