Sussex University faces a record fine of £585,000 over claims that it failed to uphold free speech and academic freedom, according to the Financial Times.

The FT said that the fine is expected to be imposed by the higher education regulator the Office for Students (OfS) after a three-year inquiry.

The investigation was prompted by the departure of Kathleen Stock who was a professor of philosophy at the university until 2021.

She became the subject of protests at the university’s Falmer campus and quit, saying that she felt unable to return to work, having been subject to bullying and harassment.

According to the FT, the regulator found “significant and serious breaches” of free speech and governance issues at Sussex University.

The news publisher quoted the OfS saying that a policy intended to prevent abuse or harassment of certain groups on campus had created “a chilling effect” that might cause staff and students to “self-censor”.

The FT also quoted Sasha Roseneil, the university’s vice-chancellor, saying that the regulator had decreed “free speech absolutism as the fundamental principle” for universities.

Professor Roseneil claimed that the regulator had “refused to speak to us”, according to the FT, and she said the fine was “wholly disproportionate”.

The university had defended Professor Stock’s right to pursue her academic work and express her “lawful beliefs”, the vice-chancellor said.

She added that the ruling made it “virtually impossible for universities to prevent abuse, harassment or bullying, to protect groups subject to harmful propaganda or to determine that stereotyped assumptions should not be relied upon in the university curriculum”.

Stock was at the centre of a row about gender identification and transgender rights and said that there was a toxic environment at the university.

Some students objected to Stock’s involvement with the LGB Alliance, an advocacy organisation that opposes “the idea that gender, the way you feel or dress, is more important than biological sex”.

According to the FT, the regulator’s inquiry focused on the university’s compliance with regulations rather than Professor Stock’s specific case.

But it found “no evidence to suggest that Professor Stock’s speech during her employment at the university was unlawful”. The academic’s work covered issues of sex, gender and individual rights.

Sussex said that universities would now be exposed to regulatory risk if they had policies to protect staff and students from homophobic, racist, islamophobic, anti-semitic or other abuse.

In a first-person piece for the Politics Home website, Professor Roseneil wrote: “Sussex will not be the last to face the challenge of a debate on gender, sex and identity that has become toxic.

“Universities across England are grappling with claims and counterclaims about academic freedom and freedom of speech regarding issues of equality, identity and inclusion.

“As the protests against the war in Gaza have shown, universities will continue to be a frontline for society’s most contentious issues.”