(Bloomberg) -- A Columbia Business School professor accused of sexually harassing a junior colleague told a federal jury he had innocent reasons for sharing chocolates and a music recommendation that included an album titled, “Sad Songs for Dirty Lovers.”

“She was a friend,” Geert Bekaert testified in federal court in Manhattan.

Bekaert, a 53-year-old tenured finance professor, was summoned to the witness stand Thursday by lawyers for the woman who’s suing him and Columbia University. Enrichetta Ravina, 42, claims Bekaert, who has worked at the school for 18 years and built a worldwide reputation for his work in international finance and empirical asset pricing, harassed her and that he and Columbia retaliated against her after she complained.

Under intense questioning by Ravina’s attorneys, he agreed that he sent numerous emails inviting her to dinners -- and later called her "insane" for wanting a schedule for their joint research. He told jurors that social activities were common in the industry, but was hesitant to say he wanted a personal relationship with her.

“I would say that it would be very hard to do joint research with somebody you really dislike,” Geert said. “So I will say that when I approached Enrichetta, I knew her already a little bit. I thought she was a nice person that would be fun to work with.”

Bekaert’s lawyers have said he was known as the "blunt Belgian" for his rudeness, but that he didn’t treat Ravina any differently than he would have treated others, regardless of their gender.

Earlier in the trial, Ravina testified that Bekaert talked to her about sex, pornography and prostitutes, occasionally touched her inappropriately and ultimately damaged her career by stalling joint research projects.

Ravina said she had been relying on data Bekaert had access to for a set of projects they had been working on together. But when she didn’t accept his sexual advances and reported his behavior to the university, she told the jury he punished her by stalling her work.

Notes from the Columbia investigator who followed up on the complaint indicate Bekaert said he would have sped up papers for someone he was romantically interested in. "Why stall papers?" the handwritten note said. "Would do opposite."

In one email, however, he acknowledged the delays could have been his fault, writing in one, "she’d really pissed me off with something, so I stopped working on it for a few months." Ravina alleges this behavior was damaging to her career and caused her to lose out on tenure.

Columbia Harassment Claim Was Deemed Woman’s Communication Fail

Bekaert’s lawyers wrapped up their cross-examination of Ravina earlier Thursday and sought to show that she participated in the relationship with her mentor and had herself to blame for not receiving tenure.

"You never told Professor Bekaert not to kiss you, right?" Edward Hernstadt, Bekaert’s attorney, asked Ravina. "You never said not to hold your hand, right?"

“Not in words,” she answered.

The defense also sought to bolster the claim that Ravina was denied tenure because her work was subpar. They presented evidence of emails in which Bekaert repeatedly advised Ravina to work on papers she was authoring alone. In one response, she wrote to him, "It was a mistake to work so much on this 401(k) crap," which was a project they had started together.

The case is Ravina v. Columbia University, 16-cv-2137, U.S. District Court, Southern District of New York (Manhattan).

To contact the reporter on this story: Sydney Maki in Brooklyn at smaki8@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Paul Cox, Joe Schneider

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