Censoring students' sentiments, as inscribed with chalk on sidewalks, could get university officials in a lot of trouble.

That's according to a letter dispatched Monday to Kenneth Hawkinson, president of Kutztown University of Pennsylvania, pointing out that that such restrictions violate the U.S. Constitution.

The letter was sent by the Alliance Defending Freedom on behalf of the members of the school's Students for Life chapter.

It came after school workers, on orders from the school's managers, scrubbed away pro-life messages chalked on open-air sidewalks.

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The university's "Posting and Chalking Guidelines," the letter contends, "violate a myriad of clearly established constitutional doctrines, thereby exposing you and all other officials involved to personal liability. First, the Guidelines could not be more explicitly content-based. As the Supreme Court recently reaffirmed, 'Content-based laws – those that target speech based on its communicative content – are presumptively unconstitutional and may be justified only if the government proves they are narrowly tailored to serve compelling state interests.'"

The letter continued, "A policy is content-based if it 'applies to particular speech because of the topic discussed or the idea or message expressed.'"

See what American education has become, in “Crimes of the Educators: How Utopians Are Using Government Schools to Destroy America’s Children.”

ADF explained that for decades, it's been established that universities violate the First Amendment "when they discriminate based on viewpoint," and the First Amendment long has protected anonymous speech.

"Last, the 14th Amendment prohibits universities from imposing policies that are 'so vague that men of common intelligence must necessarily guess at its meaning and differ as to its application.'"

The fight arose when, as part of the National Pro-Life Chalk Day, students at the school used sidewalk chalk to write positive, life-affirming messages on various sidewalks and other uncovered walkways on campus.

"The next morning, Students for Life's president, Jackie Foran, noticed that some of the group's messages had vanished. As the day went on, more vanished. She later learned KUP officials had erased all of these messages. The employees who did the erasing said they were just following orders. Students for Life tried to duplicate its message, but several of these pro-life messages were erased a second time."

The problem is with the school's policies, the lawyers explained.

The rules demand that the chalking messages "must be consistent with the items listed under the content section of this policy," which specifies the messages must be informative and cannot advocate the "infraction of any … university policy or regulation." Messages also must meet diversity requirements.

"University officials can't chalk up their censorship to 'following orders' to enforce an unconstitutional campus policy," said ADF Legal Counsel Travis Barham. "The university's chalking policy only permits messages the university agrees with. Nothing could more clearly violate the First Amendment than a policy that silences students based on whether university officials like or don't like what the students are saying."

The school guidelines specifically say the chalked messages must conform to its nondiscrimination campaign.

"Those guidelines could censor a huge number of messages that university officials don't find palatable, and, apparently, that's exactly what happened here," said ADF Senior Counsel Casey Mattox, director of the ADF Center for Academic Freedom. "While Kutztown University officials should be modeling the First Amendment for college students who will be tomorrow's legislators, judges, teachers, and voters, they are instead communicating to a generation that the Constitution doesn't matter."

The ADF letter explains: "From mandating that the 'content of the chalking must be consistent' with its content restrictions to placing those restrictions in a bulleted list under a boldfaced 'Content' heading, KUP could not possibly make it more clear that it engages in the very content discrimination that has been prohibited on campus since at least 1981.

"Based on the fact that you met with our clients and assured them that you would take action, we trust that you … will take the necessary steps to protect the constitutional rights of all your students."

The letter asks that the school issue a statement condemning the censorship "by scrub brush," "revise its guidelines to assure protection of speech rights" and hold a seminar for the individuals, departments and offices censoring Students for Life's speech.

It also asked the school to place a "litigation hold" on all email, documents and other exchanges of information, should "other alternatives" be required.

The student group condemned the censorship.

"Too frequently we see that public colleges and universities feel they can engage in censorship of a student group just because officials don’t agree with the viewpoint of those students," said Students for Life of America President Kristan Hawkins. "Kutztown University is playing favorites while stifling free speech, which is, sadly, an all-too-common response of abortion advocates who prefer to silence opposition rather than have a free exchange of ideas."

See what American education has become, in “Crimes of the Educators: How Utopians Are Using Government Schools to Destroy America’s Children.”