The 29-year-old Ph.D student faced repeated cases of sexual advances and actions starting in 2014. View Full Caption Wikipedia/Andrew Chen

MORNINGSIDE HEIGHTS — A Columbia grad student is suing the university for failing to do anything about a prominent history professor she accused of sexually harassing her for years.

"There were a lot of factors that went into making this very difficult decision," the plaintiff told DNAinfo New York about her lawsuit. "I certainly felt like it was a last resort, and I tried many times to bring his behavior to the attention of the administration without success."

In a lawsuit filed in Manhattan federal court Monday and first reported by the New York Times, the 29-year-old victim claims the sexual advances by Columbia history professor William V. Harris, 79, began shortly after their initial meeting at a 2014 spring semester lecture series. The student was only 26 at the time when Harris agreed to formally mentor her, according to the lawsuit.

The victim, who is not named in the suit, says the harassment started with inappropriate and unwelcome comments about her appearance before escalating to sexual assault.

In one incident, the student was felt "up and down her back in a sexualized manner" by Harris, and in another he "suddenly and without warning or permission" put his mouth on her breast, the lawsuit alleges. The professor also took the plaintiff to what was supposed to be a dinner to discuss her career and "instead spoke about her appearance and his desire for sexual intercourse with her," the suit states.

In another incident, Harris invited her to a "strictly professional" trip and told her he had booked separate hotel rooms, according to the suit. However, the student claims he only booked a single hotel room and continued to press her for sex.

The harassment forced the victim to withdraw from Columbia for the 2015-2016 academic year, the lawsuit claims, and when she returned in 2016, she refused to have any contact with Harris. But up until the spring of 2017, Harris disparaged the victim to her colleagues and called and emailed her, claiming that she failed "to have the courage to stay loyal to [her] old friend," the suit says.

When the victim complained to Columbia's administration about Harris, the school failed to take substantive action, the suit says. The student requested that Harris have restricted access to the department in which she studied, but the school's Title IX Coordinator and associate vice president, Marjory Fisher, could only offer her office as shelter for the student during times when Harris had scheduled classes, the suit alleges.

The lawsuit added that the school should have been aware of Harris's inappropriate behavior, as many professors were not surprised at the student's complaints. Since filing suit, the student said she's heard from many other victims going back decades.

"Although Columbia pays lip service to the ideals of a safe campus environment, the University has a track record of violating Title IX when responding to reports of sexual misconduct," the complaint states.

“I have grave concerns that he is still actively teaching graduate and undergraduate students and participating in student life,” the victim told DNAinfo. “It compromises their educational environment and safety, and as such, I believe there should be measures to be put in place.”

When reached for comment about the lawsuit, the university offered a statement that declined to address legal matters.

"We treat any claims of harassment or other gender-based misconduct in our community with the utmost seriousness," the statement read. "But we do not comment in the press on allegations made in legal complaints."

Harris did not return a request for comment.

The student is demanding that a jury, which would decide monetary damages, hear the case. She said her priority was to ensure that future cases be more seriously addressed by the university.

"I feel I have a strong moral imperative and a sense of responsibility for other students who might come after me," she told DNAinfo.

The victim's case bears similarities to that of Emma Sulkowicz, a Columbia undergrad who, frustrated with the university's unwillingness to address her rape allegations against a fellow student, carried a mattress around campus in 2013. The student she accused, Paul Nungesser, was later deemed not responsible by the university. Nungesser filed a gender discrimination lawsuit in 2015 following the incident and eventually settled with the university in July of this year.