Virginia Lt. Gov. Justin Fairfax has been placed on leave by his law firm as it investigates the sexual assault allegations against him.

Washington, D.C.-based Morrison Foerster “has retained outside counsel to conduct an investigation. During the investigation, Justin Fairfax has taken a leave of absence from Morrison & Foerster. Justin has agreed to cooperate with the firm’s investigation,” Larren M. Nashelsky, chairman of the firm, said in a statement.