During my recent week as a “practitioner in residence” at Duke University, speaking to a wide range of faculty and students, I felt more than welcome on a campus where my conservative viewpoint was far from the mainstream.

But perhaps my experience wasn’t the norm. After all, I wasn’t a student who might have reason to worry that expressing a political opinion contrary to that of my professor could harm my grade or standing in class. And I wasn’t a professor who might have reason to worry that a sentence uttered in class on a controversial topic might be taken out of context and then promoted online to embarrass me or damage my career.

In other words, I wasn’t particularly worried about adverse consequences when I expressed my opinions at Duke. I figured that if someone disagreed with me, and chose not to engage me in a respectful dialogue but to go after me later in some fashion, there wasn’t a whole lot that could be done to me.

As I indicated, my week at Duke produced no such controversies, at least to my knowledge. But I did have quite a few students say to me, during class or in offline conversation, that I had expressed opinions they had not yet heard during their time at the university, and that they appreciated the intellectual stimulation that came from it.

Surveys of university faculties show that they overwhelmingly vote Democratic and increasingly hold progressive views far removed from those of the median voter. Although the resulting lack of intellectual diversity on campuses is a problem, it doesn’t necessarily have to be a crisis. Good teachers can take steps to ensure that their students are exposed to a variety of perspectives in the classroom. And if freedom of speech and assembly are protected, universities can welcome other voices to campuses, in the form of guest speakers or visiting lecturers, to further diversify the conversation.

Unfortunately, too many educational institutions fail to protect those freedoms on campus, including right here in North Carolina. According to the Foundation for Individual Rights in Education (FIRE), only one of the campuses of the University of North Carolina system — UNC-Chapel Hill — fully protects freedom of speech, earning it a “green light” on FIRE’s rating system. Another 11 campuses get yellow lights, meaning that their free-speech protections are spotty or incomplete, while UNC-Greensboro, N.C. Central University, Winston-Salem State University, and the School of the Arts merit red lights from FIRE.

Private schools such as Duke aren’t legally subject to the First Amendment and other constitutional provisions that protect personal freedoms from government encroachment. But as institutions devoted to education, scholarship, and public service, they certainly ought to be bastions of open, unfettered discussion and debate. All too often, however, they are places where conservative speakers are shouted down or not invited in the first place, where students are allowed to express themselves only in limited physical or online “speech zones,” and where faculty are subject to intense pressure to conform to the prevailing ideological prejudices of the Left, as evidenced by the recent dispute at Wake Forest University about a research institute partially funded by the Charles Koch Foundation.

When it comes to public campuses, at least, Lt. Gov. Dan Forest and a number of like-minded legislators in the General Assembly have decided that the protection of intellectual freedom can’t simply be left to the institutions themselves. Two state representatives, Chris Millis and Jonathan Jordan, have filed House Bill 527. It would establish a system-wide policy protecting freedom of speech, noting that it is not the universities’ job to shield people from opinions they may not like. While the right to protest would be fully protected, the bill makes it clear that shouting down invited speakers or otherwise disrupting campus events is an attack on freedom of speech, not an exercise of freedom of speech, and will subject the would-be censors to disciplinary action.

Freedom is worth fighting for. Let’s start with college campuses.

John Hood is chairman of the John Locke Foundation and appears on the talk show “NC SPIN.” You can follow him @JohnHoodNC.