Some students said they did not believe Mr. Sullivan was fit to serve as a dean of a residential college and at the same time represent Mr. Weinstein, who has been accused by more than 80 women of sexual harassment and, in some cases, assault.

In his first public remarks, Mr. Sullivan said in a phone interview on Monday that he did not anticipate the level of backlash he has received. He has a long history of taking on high-profile and, at times, controversial clients, as well as representing students who have been victims of sexual assault, he said.

“Lawyers are not an extension of their clients,” Mr. Sullivan said. “Lawyers do law work, not the work of ideology. When I’m in my lawyer capacity, representing a client, even one publicly vilified, it doesn’t mean I’m supporting anything the client may have done.”

Some students disagree. Dozens of protesters, some with tape over their mouths, protested last month in front of the administration building, holding signs that said “Remove Sullivan” and “#MeToo.” About 270 people have signed an online petition calling for him to resign from his faculty dean position.

“Do you really want to one day accept your diploma from someone who for whatever reason, professional or personal, believes it is O.K. to defend such a prominent figure at the center of the #MeToo movement?” one student, Danu Mudannayake, wrote in the petition.