Columbia hasn’t defended its handling of the case, or the outcome, beyond rejecting Sulkowicz’s appeal. To Nungesser, that’s what is unfair. “They have a process in place, which I followed to the letter,” he told me. “I had everything to lose in it. And it’s been worth nothing. Absolutely nothing.” Columbia officials think that declining to comment about publicized cases is necessary to encourage other students to go to rape counselors or through the disciplinary process. “Students should be confident that the university is not going to talk about these cases in any respect,” said Suzanne B. Goldberg, a Columbia law professor who is the executive vice president for university life.

Nungesser says that he prevailed despite Columbia’s refusal to consider his best evidence: Facebook messages that he and Sulkowicz sent to each other before and after the alleged rape. The messages sound friendly: “I feel like we need to have some real time where we can talk about life and thingz/because we still haven’t really had a paul-emma chill sesh since summmmerrrr,” Sulkowicz wrote a few days after the night in question. After The Daily Beast published the exchanges, Sulkowicz explained them to the website Jezebel, recalling, “I’m being irrational, thinking that talking with him would help me.”

Sulkowicz says some of the Facebook messages were admitted as evidence. Her recollection is at odds with that of a graduate student who attended the hearings with Nungesser, as his designated “supporter,” and said the messages were not included. In court, the Facebook messages surrounding the night of the alleged rape would probably be admitted in a criminal case as relevant, according to Deborah Tuerkheimer, a Northwestern University law professor, and the alleged victim would also have the chance to explain them. (This is also what Columbia’s policy now appears to provide, though the rule was somewhat different at the time of the hearing.)

Deciding which evidence to admit is a minefield that universities have to pick their way through. For example, Columbia says it does not allow “prior conduct violations” into evidence unless the alleged assailant has been found “responsible” for them. (That’s the word universities use instead of “guilty.”) State courts would usually exclude evidence of prior sexual misconduct in a criminal sexual assault case, Tuerkheimer says, though federal courts may admit it.

The distinction is the subject of another dispute over process between Nungesser and Sulkowicz. At the time Sulkowicz came forward, two other women accused Nungesser of different forms of sexual misconduct. He was found not responsible. She says the panel at her hearing did not consider the other allegations against him. Nungesser’s father said the allegations were mixed together. (To briefly summarize them, Nungesser’s girlfriend from freshman year said their monthslong relationship was abusive and included nonconsensual sex; the case was dropped after she stopped answering Columbia’s emails over the summer. A second woman, who lived at the same literary society as Nungesser, said he grabbed her in an empty room during a party there. A third accusation against Nungesser, brought in 2014, was dismissed earlier this month.)

Nungesser denies all the allegations. He was initially found responsible in the party incident, but he was granted an appeal, and the finding against him was overturned. The appeal raises another issue with the rules. At the time it took place, the university said that a supporter at a hearing had to be a current Columbia faculty member, administrator or student. The woman who said Nungesser grabbed her at the party had graduated, and so had the close friends she would have chosen as supporters, she told me. The lack of emotional support was one reason she didn’t want to go through a rehearing.

This is an issue Columbia has tried to address. Last summer, the university announced significant changes to its sexual assault and harassment procedures. Students are now permitted to bring a lawyer to their hearings, and if they can’t afford an attorney, the university will provide one. The university also hired new investigators and other staff members and gave training on how to hear cases to the administrators who serve as panelists. Columbia also started a “sexual respect initiative” aimed at prevention.