NEW YORK (CBSNewYork/AP) — Citing the importance of the First Amendment, Columbia University asked a judge Friday to reject a student’s lawsuit alleging the school failed to protect him after a onetime friend called him a “serial rapist” and carried a mattress around campus to protest sexual abuse.

The university said in a filing in U.S. District Court that it was a “fatal flaw” in Paul Nungesser’s lawsuit that he failed to sufficiently claim intentional gender discrimination by Columbia. His lawsuit alleged that the university’s actions caused him to face gender discrimination and defamation during the last school year and damaged his job prospects.

Student Emma Sulkowicz claimed Paul Nungesser raped her in 2012.

She alleged the university never took action against him and carried a mattress around campus to draw attention to sexual assaults at the school, in a project titled “Carry That Weight.”

Nungesser, a German citizen, sued the university this year, saying it effectively sponsored attacks against him by letting Sulkowicz obtain class credit with her mattress-toting project that was designed to draw attention to her claims against him for a year leading up to commencement proceedings.

The lawsuit said Sulkowicz has repeatedly and publicly called him a “serial rapist,” resulting in national and international media attention. The lawsuit sought unspecified damages.

Columbia’s lawyers wrote that the lawsuit suggested that the university was obligated “to silence Ms. Sulkowicz, preventing her from speaking publicly on the issue of sexual assault on college campuses — an issue of national concern.”

“However, at colleges and universities like Columbia the `atmosphere of speculation, experiment, and creation is essential to the quality of higher education,”’ the lawyers wrote, adding that federal laws against gender discrimination were “never intended to curb this cherished tradition of vigorous, even raucous, debate.”

They said letting Sulkowicz proceed with her project was a “decision at the heart of academic freedom.”

“This is especially true here, where Ms. Sulkowicz was a visual arts major and inherently subjective judgments of aesthetic value were at issue,” the lawyers said.

Sulkowicz has argued her case was badly mishandled by the school disciplinary panel after she the alleged rape in 2013. After a university investigation, a school panel heard Sulkowicz and Nungesser testify before clearing Nungesser of the accusation.

Sulkowicz, who has been lauded for her stance on the issue, appeared as Sen. Kirsten Gillibrand’s guest to the year’s State of the Union speech.

Sulkowicz was not named in Nungesser’s suit, but Columbia President Lee Bollinger and a professor who approved the protest as part of Sulkowicz’s thesis project are.

Andrew T. Miltenberg, a lawyer for Nungesser, said the university “shamefully bowed to social pressure” and turned its back on his client.

“In this instance, the disciplinary system worked correctly at Columbia,” he said in an email. “That still was not enough to save an innocent person from the wave of public sentiment regarding assaults on campus. Paul Nungesser quickly became a convenient scapegoat, a whipping boy, and Columbia not only stood idly by, but often participated in the attacks on Paul Nungesser. There is no amount of legal theory that can save Columbia from that reality.”

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