Three Harvard graduate students filed a lawsuit against the university on Tuesday, accusing the school of ignoring multiple claims that a respected anthropology professor had sexually harassed a number of students for years.

The women, Lilia Kilburn, Margaret Czerwienski and Amulya Mandava, alleged that anthropology professor John Comaroff, “kissed and groped students without their consent, made unwelcome sexual advances, and threatened to sabotage students’ careers if they complained,” The New York Times reported.

In an interview with the Times, Kilburn disclosed an inappropriate interaction with Comaroff, her adviser, on her first day at the school. She alleged that on an earlier campus visit, Comaroff “kissed her on the mouth.” After the questionable moment, Kilburn said she felt it necessary to disclose she was a lesbian by bringing up a vacation with her partner.

Comaroff, whose anthropological focus as a professor is South Africa, then replied in what was explained as “a tone of enjoyment” that in Africa, lesbians could be subjected to “corrective rape” or killed, The Times reported.

Czerwienski and Mandava are being listed in the lawsuit as whistleblowers who claim that they are victims of Comaroff in the sense that he intimidated them by threatening their academic careers if they reported him.

Other allegations dating back to 2012 about Comaroff were allegedly known by the school, and were originally reported on in both the student newspaper The Harvard Crimson and The Chronicle of Higher Education.

Harvard has held Comaroff responsible for “verbal conduct that violated policies on sexual and gender-based harassment and professional conduct,” placed him on administrative leave for the spring semester and banned him from teaching selected courses until the next academic year.

However, because the university has not found him responsible for “unwanted sexual contact,” the women feel that this is effectively denying their allegations of sexual harassment.

Comaroff’s leave has led prominent faculty members from Harvard and other schools to stand up for him by signing an open letter that not only questions the investigation, but also vouches for him as an “excellent colleague.”

Comaroff’s lawyers told the Times that he denies any sexual harassment and his alleged “rape comment” was “motivated only by concern for Ms. Kilburn’s well-being and had no romantic or sexual intention, but that the advice nonetheless constituted sexual harassment.” He also denied that finding, claiming it impairs academic judgment on advising students about safety issues.

In the letter signed by faculty members, the signers agree with Comaroff and say that they “would also feel ethically compelled to offer the same advice.”