A University of Michigan student is suing the school and renowned opera singer David Daniels, also a U-M professor, alleging Daniels sexually assaulted him. The lawsuit also alleges the university knew for years of Daniels' sexually harassing behavior and did nothing.

The suit, filed by Andrew Lipian in federal court Wednesday, details a history of Daniels making sexually suggestive comments and then, one night in March 2017, drugging and sexually assaulting Lipian.

Daniels could not be reached for comment Wednesday afternoon.

"Shortly after allegations about Professor Daniels from years earlier in another state were shared publicly, the university made a statement, Aug. 22, that Professor Daniels had agreed to take a leave of absence and would not be teaching at U-M this fall," U-M spokesman Rick Fitzgerald said. "All reports to the Office for Institutional Equity that allege actions that may be criminal in nature are transmitted to law enforcement for review.

"The university's standard practice with any allegation that could be criminal in nature is to defer to the law enforcement investigation before commencing an OIE investigation. A criminal investigation takes precedence over an investigation of a possible policy violation."

Daniels has already been accused by at least one other person of similar behavior. He and his partner have been accused of raping a singer after a performance at the Houston Grand Opera in May 2010. That accusation, which was made this August, is still under investigation by police. Daniels and his partner have denied the accusations. Daniels went on leave from his teaching job at U-M earlier this year when the accusation came to light.

"The university has a great deal of work to do with regard to sexual harassment training and oversight of its faculty," Lipian's attorney, Deborah Gordon, said in an email to the Free Press. "Its written policies recognize that 'sexual harassment most often occurs when one person has actual or apparent power or authority over another.' But here, a professor who was regarded as a major star openly discussed his sexual thoughts and activities. He felt entitled. He regularly sent my client sexually explicit material and messages and assaulted him. He was apparently hired with little vetting of his ability to conduct himself properly around students and received no training or oversight. This lawsuit is the result."

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Lipian said he came to U-M with a dream of becoming a countertenor singer. Daniels is also a countertenor singer with an extensive professional opera background.

Not only did Lipian take classes with Daniels, he also met with him weekly for private voice lessons.

According to the lawsuit, Daniels, during those sessions, began making sexually suggestive comments to Lipian, who claims in the suit it was well-known to U-M administrators that Daniels routinely made such comments.

Lipian also said he received texts from Daniels asking for videos of himself masturbating and received videos of Daniels masturbating.

Lipian said in the suit he is heterosexual and married. Daniels is openly gay.

Then came March 24, 2017, when Daniels invited Lipian to his apartment to watch “Ru Paul’s Drag Race” "because he was 'lonely' and wanted to discuss (Lipian's) 'career,'" the suit says.

"Plaintiff was served several drinks of bourbon," the lawsuit alleges. "When he said he was tired and needed sleep for a performance the next day, Daniels handed him what he said was a Tylenol PM but was actually the sleep medication Ambien. Daniels then removed (Lipian’s) clothes, forced himself upon (Lipian) and groped and touched his genitals and face."

The lawsuit alleges that in May 2018, Daniels told Lipian someone had sent an anonymous letter to the school stating that Daniels had “come on” sexually to two students

"He later advised Plaintiff that a University administrator told him the letter was inconsequential and probably false," the suit alleges.

The suit says another faculty member became aware of the assault in August 2018 and reported it to the university's Title IX office, as legally required.

The suit alleges no investigation has ever been launched and the student has never been contacted by the university.

The suit says U-M was "deliberately indifferent to Daniels' actions.

"Defendant knew that Daniels was a renowned singer and that he had particular power to intimidate, entice, coerce and/or manipulate students. In fact, the University ignored warnings about his behavior precisely because he was valuable to it as 'today’s gold standard among countertenors,' as described on its website," the lawsuit says.

Daniels has performed with many metro Detroit organizations over the past decade, including University Musical Society and Michigan Opera Theatre. He was originally scheduled to perform as part of the Detroit Symphony Orchestra’s current season on April 27 to April 29 as part of the Vivaldi’s “Gloria” program, but is no longer scheduled to be a part of the production, DSO spokesman Matt Carlson told the Free Press.

Contact David Jesse: 313-222-8851 or djesse@freepress.com. Follow him on Twitter: @reporterdavidj