Sen. Kirsten Gillibrand is calling for the Justice Department to investigate the U.S. Olympic Committee in light of the serial sexual abuse committed by gymnastics team doctor Larry Nassar.

In a letter to Attorney General Jeff Sessions, the New York Democrat said while some gymnastics officials have resigned after more than 150 women and girls abused by Nassar publicly shared their stories, it was not enough.

“His crimes were facilitated by a culture of silencing victims and valuing a doctor over the vulnerable children he was supposed to heal,” the New Democrat wrote. 

Gillibrand’s letter comes amid a report from the New York Times that the FBI knew about Nassar’s abuses as early as 2015 and let a probe into him drag on for a year. The Olympic Committee reportedly learned of the abuse around the same time.

“The U.S. Olympic Committee had a moral duty to act when informed of a possible crime. Their inaction resulted in the abuse of even more young women and girls,” Gillibrand wrote. “It is incumbent on the Department of Justice to investigate whether there was a legal duty as well.”

The Nassar case has captured lawmakers’ attention. The Senate last month approved by voice vote new legislation to impose reporting requirements for amateur sports like gymnastics. The House then passed an amended version of the legislation.

Gillibrand is also a co-sponsor of legislation by Republican Sen. Joni Ernst of Iowa and Democratic Sen. Jeanne Shaheen of New Hampshire to establish a special committee to investigate USA Gymnastics and the U.S. Olympic Committee for their role in what they called negligent behavior.

Gillibrand’s letter requests that the Department of Justice “examine the extent to which other parties have failed in their duty and should be held responsible” for allowing Nassar’s abuse to continue occurring.

Nassar, who is currently serving a separate 60-year federal prison sentence on child pornography charges, was convicted of criminal sexual misconduct for abusing his patients.