Bascom Hall on the campus of the University of Wisconsin. (BigStock Photo)

Conservative media commentator Ben Shapiro was just a few minutes into a lecture at the University of Wisconsin last fall when more than a dozen student protesters rose from the audience and began chanting “shame!” and “safety!” in hopes of drowning him out.

Some of the protesters made their way to the front of the room and stood in front of Shapiro, a former Breitbart News editor who was giving a speech titled “Dismantling Safe Spaces,” as the university’s independent student newspaper reported at the time. Eventually, campus police arrived and the group exited, allowing Shapiro to carry on.

Under a new bill approved Wednesday night by the Wisconsin State Assembly, such student protesters in the UW system could be suspended or even expelled if they repeatedly disrupt campus speakers they disagree with.

The Republican-backed legislation, called the Campus Free Speech Act, is part of a national effort by conservative groups to crack down on protests intended to silence controversial speakers on liberal college campuses. Similar measures have been enacted in Colorado and introduced in Michigan, North Carolina, Virginia and California.

Demonstrations like the one that interrupted Shapiro’s speech last fall have become an increasingly common sight at universities around the country as debate has roiled over how to curb hate speech while protecting free expression and intellectual diversity. Some demonstrations have turned violent, like the recent protests and riots in Berkeley, Calif., that shut down a planned lecture by conservative provocateur Milo Yiannopoulos.

After nearly four hours of debate Wednesday night, Wisconsin lawmakers approved the Campus Free Speech Act in a 61-36 vote along party lines, with no Democrats supporting it. The bill now heads to the State Senate.

Rep. Jesse Kremer, the lead sponsor, said he introduced the bill in response to “situations where students’ free speech rights have been taken away.” The goal, he said, was to make the state university’s campuses more civil for people of all political orientations.

“We don’t want to get to the point of having situations in Wisconsin like Berkeley,” Kremer, a Republican from Kewaskum, Wis., told The Washington Post. “It’s not meant to hurt anyone. People are still allowed to protest and disagree. It’s that the person in a forum has the right to get their point across without being disrupted.”

But assembly Democrats have warned that the bill could have a chilling effect on campus speech if it becomes law.

“Our colleges and universities should be a place to vigorously debate ideas and ultimately learn from one another,” Rep. Lisa Subeck, a Democrat from Madison, told the Milwaukee Journal Sentinel. “Instead, this campus gag rule creates an atmosphere of fear where free expression and dissent are discouraged.”

Under the legislation, students in the UW system could face a disciplinary hearing if they receive two or more complaints about disruptive conduct during a speech or presentation. If a student is found responsible for “interfering with the expressive rights of others,” the bill would require that the student be suspended for a minimum of one semester. A third violation would result in expulsion. Anyone who feels their expressive rights are violated can file a complaint.

The legislation, based on a model bill from the conservative Goldwater Institute, would require the UW system to remain neutral on public controversies and require the Board of Regents to report annually on disciplinary matters and “free expression barriers and disruptions.” It also would require institutions to explain their free speech rules and policies in their orientation materials.

Republican Gov. Scott Walker has expressed support for the measure.

“To me, a university should be precisely the spot where you have an open and free dialogue about all different positions,” he told WISN in April. “But the minute you shut down a speaker, no matter whether they are liberal or conservative or somewhere in between, I just think that’s wrong.”

Others voiced skepticism. Democratic Rep. Cory Mason told the Associated Press the bill’s requirements would “neuter” universities from “having any stance on things.” And one Republican, Rep. Bob Gannon, said he worried that liberals could use it to silence conservative students seeking to protest abortion or gun control.

“I’m afraid it’s going to intimidate students into silence — conservative students into silence,” he told the Journal Sentinel.

The legislation comes at a time of extraordinary tension on college campuses around the country. Many conservatives accuse liberal students and outside agitators of suppressing free speech by demonstrating — sometimes violently — against controversial speakers. Those protesting often contend that such speakers are engaging in unprotected hate speech and threatening the safety of minority students, women and others through their words.

Several weeks after a violent mob shut down Yiannopoulos’s lecture in Berkeley, a planned lecture there by conservative writer Ann Coulter was canceled over threats of unrest. Scuffles also broke out in April during a speech by white nationalist Richard Spencer at Auburn University in Alabama. And in May, angry protesters at Middlebury College cut short a speech by the conservative scholar Charles Murray, author of a widely criticized book linking I.Q. scores to race, and badgered him as he tried to exit.

Correction: An earlier version of this story erroneously stated that California had enacted a campus free speech bill. Such legislation has been introduced in the state but not approved.

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