For more than three hours Tuesday afternoon, four members of the Key of David Christian Center lobbed insults and verbal attacks at members of the University of Maryland community gathered at McKeldin Mall.

The four demonstrators held up signs proclaiming “Feminists support pedophilia” and “Jesus or Hellfire.” They hurled transphobic slurs, and told at least one female student she might get raped for wearing leggings.

On social media, many said the demonstrators should have been denied a space on campus due to the hateful nature of their speech. But under the First Amendment, protestors are allowed to remain on the campus due to its status as a public forum.

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Martin Kobren, an adjunct government and politics professor at this university who helps teach a First Amendment class, said moving the protestors based on the content of their speech would have constituted a violation of their civil liberties.

“One of the base rules of the First Amendment is that someone cannot discriminate based on the basis of content,” he said.

Hate speech — something Kobren said is “awfully hard to define” — is permitted under the First Amendment.

So, though he didn’t agree with the demonstrators, freshman Paul Rapuzzi said he thought they had a right to be there.

“I hate hearing them say that stuff, but obviously I don’t think they should be kicked out for just saying what they believe, even if it’s pretty bigoted,” the government and politics major said.

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But Kari Maygers, a freshman architecture major, said the demonstrators’ speech should have been regulated because of the harm it was causing passersby.

“Being super aggressive and derogatory towards someone else is definitely pushing that boundary,” Maygers said.

When asked for comment, a University Police spokesperson deferred to the university’s Office of Strategic Communications.

It’s not the first time there’s been a demonstration like this on campus. Kobren said during his time at the university as an undergraduate in the 1970s, evangelical pastors with similar messages would often come preach on the campus, and students would gather to question or jeer at them.

In November 2002, members of the Westboro Baptist Church — another radical religious group known for its hateful messaging — came to the university to protest a production of The Laramie Project, a play that described the reactions to the murder of gay University of Wyoming student Matthew Shepard.

Students then protested the church, too, producing buttons that said “Hate is not a UMD value,” and dressing in angel costumes to contrast Westboro’s infamous anti-LGBT signs.

And in 2016, former Breitbart News editor Milo Yiannopoulos, who was banned from Twitter earlier that year for making racist comments, was originally set to speak on campus. Before it was scheduled to happen, the event was canceled due to high security fees.

On Tuesday, after hours of student protest — including songs, snide remarks and stripping — the demonstrators left on their own accord.

“I really enjoyed seeing the counterprotest,” Rapuzzi said. “It was a handful of bigoted people coming in and just being jerks about their opinion, and seeing hundreds of kids on campus just making fun of that thought — I thought it was great.”

In a statement, the university’s diversity and inclusion vice president, Georgina Dodge, called the demonstrators’ statement “disparaging and hateful,” adding that University Police were in attendance to “protect participants’ safety and constitutional rights.”

“This peaceful counter protest was student-led, and it sent a strong message,” Dodge said in the statement. “We salute you.”

Staff writer Eric Neugeboren contributed to this report.