But Dr. Gilad said that when it was contacted, Princeton said there had been no sexual harassment investigation of Dr. Lieb while he was there. He said efforts to find out more about what prompted Dr. Lieb’s departure proved fruitless. A Princeton spokeswoman said the university does not comment on personnel matters.

Faculty at Chicago said that Dr. Lieb had told them during the interview process that Princeton faulted him for not informing them about a complaint of unwanted contact filed against him at North Carolina, where he had taught for 13 years. But he told them he had seen no reason to do so because the investigation had not found evidence to support the claim.

Subsequently, he gave permission to Princeton to examine his personnel file. Chicago, too, received permission to look at the file, Dr. Gilad said, adding that the examination of the records did not raise red flags.

Separately, Dr. Gilad acknowledged, during the interviews of Dr. Lieb, he admitted that he had had a monthslong affair with a graduate student in his laboratory at the University of North Carolina.

At Chicago, the hiring committee struggled, Dr. Gilad said, to balance a desire to protect students with a desire not to convict someone without evidence. He said Dr. Lieb had not been found guilty of any offense at North Carolina. The department of human genetics voted unanimously to hire him.

“It’s hard to say this in retrospect,” Dr. Gilad said, “but what’s the value of investigating anything if an unsubstantiated allegation itself invalidates the candidate?”

But Joe Thornton, a faculty member in the department who raised objections before the vote, said in an interview, “I don’t think that’s the right standard to use.” He added, “It may be a legal standard, but we should be capable of making more nuanced judgments about the environment we’re creating for human beings that are doing and learning science.”