A professor is suing officials at his small public university in Ohio after receiving a written warning for violating its nondiscrimination policy by not addressing a transgender student using the gender terms preferred by the student.

Nicholas Meriwether, a philosophy professor and evangelical Christian, filed a federal lawsuit this month against officials at Shawnee State University in Portsmouth, roughly 85 miles south of Columbus. He contends that officials violated his constitutional rights by, among other things, compelling him to speak in a way that contradicts his religious beliefs.

“In January 2018, a male student demanded that Dr. Meriwether address him as a woman because he identified as such and threatened to have Dr. Meriwether fired if he declined,” the lawsuit, filed on Nov. 5, states. “To accede to these demands would have required Dr. Meriwether to communicate views regarding gender identity that he does not hold, that he does not wish to communicate, and that would contradict (and force him to violate) his sincerely held Christian beliefs.”

After the student, a transgender female, complained to the university, the lawsuit alleges the school “punished” Meriwether for “expressing views that differ from its own orthodoxy and for declining to express its mandated ideological message.”

“Continuing in their role as the self-appointed grammar police, Defendants threaten to punish him again if he continues to express his views,” the suit continues. “Under their policies, all professors must refer to each student — both in and out of class — using whatever pronouns the student claims reflect his gender identity.”

The lawsuit claims “the number of potential gender identities is infinite” and states there are “over one hundred different options currently available.”

Meriwether, who has worked at the university since 1996, argued he didn't discriminate and that he treated the student like "other biologically male students." He unsuccessfully challenged his reprimand in a grievance process.

The Alliance Defending Freedom (ADF) filed the lawsuit on Meriwether’s behalf. The Arizona-based conservative Christian law firm has a decadeslong track record of litigating against lesbian, gay, bisexual and transgender rights, and it has been labeled an anti-LGBTQ “hate group” by the Southern Poverty Law Center, a designation ADF disputes.

The university would not comment on the lawsuit but said in a statement that it values “freedom of expression” and provides “an educational and work environment that is free from discrimination, retaliation and harassment.”

“We expect that as this case progresses, and details come to light, it will become clear that we made decisions in an effort to both respect our faculty member’s deep-rooted religious beliefs and our student’s right to equal treatment in the classroom,” the statement continued.

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