MILWAUKEE – There was a time when open discussion and debate were cornerstones of the university experience.

But runaway political correctness is killing the concept of free expression, even at private, religious universities.

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Just ask Professor John McAdams of Marquette University.

In 2014, McAdams was suspended with pay and banned from campus after publicly criticizing an assistant instructor who prevented an open discussion of gay marriage in class, according to the Milwaukee Journal Sentinel.

The instructor, Cheryl Abbate, reportedly told a student that he would not be allowed to make “homophobic” statements in her classroom, the Journal Sentinel reported.

At first McAdams was told he was going to be fired for criticizing the instructor. Now he’s learned that he can be reinstated, but only if he admits, within two weeks, that he was wrong, the newspaper reported.

So McAdams has a miserable choice to make. He can sign on to the idea that free speech and discussion should not be allowed in Marquette classrooms, or lose a source of his livelihood.

The decision to suspend McAdams through the fall semester of 2016 – without pay but with benefits – was based on a recommendation from a Faculty Hearing Committee that reviewed the case, news reports said.

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The faculty committee found that McAdams had been punished without required due process. And it never recommended that he should be compelled to admit he was wrong for openly expressing his beliefs, according to a press release from the Wisconsin Institute for Law and Liberty (WILL).

“While (the university) followed the recommendation that (McAdams) be suspended, it also imposed a requirement that, within two weeks, he admit his ‘guilt,’” the WILL statement said. “If he refuses to do so, he will not be reinstated. Such a requirement of self-abasement and compelled speech was not recommended by the Faculty Hearing Committee.”

WILL criticized the Faculty Hearing Committee for failing to provide clear guidance on the issue of academic freedom. McAdams’ case leaves other Marquette instructors in the dark about what they are allowed to say in the classroom or any sort of public forum.

“In its lengthy report, the Faculty Hearing Committee gave lip service to academic freedom but made it subject to a multi-factor after-the-fact balancing test that would leave members of the university with no real guidance or protection other than the sufferance of their colleagues,” the press release said. “In other words, University faculty retain freedom of speech only so far as their colleagues are willing to tolerate it.”

Gay marriage is clearly a legitimate topic of public discourse. Some favor it and some oppose it. But apparently some believe that those who oppose it should be muzzled.

Are the four U.S. Supreme Court Justices who recently argued and voted against legalized gay marriage guilty of homophobia? Should they have been prevented from expressing their opinions during the court’s deliberation of the issue?

In his statement regarding the censorship of the student in Abbate’s classroom, McAdams summed up political progressives’ approach to free speech:

“Opinions with which they disagree are not merely wrong … but are deemed ‘offensive’ and need to be shut up,” he wrote, according to the Journal Sentinel.

It appears McAdams hit the nail on the head. That’s scary in a nation where free thought and expression are supposed to be cherished and protected principles.