The N.C.A.A. sent a letter of inquiry to Michigan State University, formally opening an investigation into how the university handled the case of Lawrence G. Nassar, the doctor who sexually assaulted scores of female athletes.
Dr. Nassar spent decades on the faculty at the university and treated its athletes, as well as members of the United States national gymnastics team.
“The N.C.A.A. has requested information from Michigan State about any potential rules violations,” Donald M. Remy, the association’s chief legal officer, said in a phone interview Tuesday evening.
N.C.A.A. bylaws require colleges to protect the health, safety and well-being of athletes.