Under the terms of the law firm’s contract, the lawyers were to defend the university in civil lawsuits, facilitate “cooperation” with law enforcement and provide “counseling on any internal reviews conducted to make sure they are carried out in a manner that will best assist the university’s response.”

Though some women say they told university employees about abuse years ago, Mr. Fitzgerald wrote in December that no one who knew Dr. Nassar believed he could be capable of such behavior. “It is clear that Nassar fooled everyone around him — patients, friends, colleagues, and fellow doctors at M.S.U.,” Mr. Fitzgerald wrote.

Over the months since they hired Mr. Fitzgerald, 57, and his team of lawyers, Michigan State officials have highlighted his review — sometimes noting Mr. Fitzgerald’s involvement by name — as a sign of the seriousness of their response. Lou Anna K. Simon, who resigned as president on Wednesday, had portrayed the university’s review as a robust and “tireless effort” that would go on as long as needed. “Even as we examine — through both criminal investigations and a thorough internal review — how something so abhorrent happened here and went on for so long, we are taking action,” she said last April.

Dr. Nassar was sentenced to 40 to 175 years in prison on Wednesday, after days of wrenching testimony from more than 150 women who have accused him of molesting them while he was a doctor for Michigan State and the national gymnastics team. The president stepped down hours later.

By week’s end, Michigan State’s athletic director, Mark Hollis, had also resigned. And two outside agencies — the federal education department and the Michigan attorney general — had begun what the university’s critics hoped would be truly independent investigations into its handling of Dr. Nassar.

Bill Schuette, the state attorney general, said on Saturday that his office was leading a review that would “put a bright light in every corner of the university.” He promised that the investigation would look “from the president’s office down” for answers about what had happened.

Mr. Schuette also said he would ask the university’s trustees to have Mr. Fitzgerald “turn over all information he has gathered in the course of his work.”