Cornell University said it is suspending all “parties and social events” at fraternity houses for the rest of the academic year amid an uproar over a former student’s allegation that she was sexually assaulted by members of the campus Chi Phi chapter nearly two years ago.

Michael I. Kotlikoff, Cornell’s president, also announced that the Ivy League institution would bring on “experienced, trauma-informed criminal investigators” to review allegations of sexual assault on campus.