James Craig Summers, 55, of Burke, was arrested Tuesday and charged with forcible sodomy, Prince William County police said.
Summers, a patrol officer in the Reston District in Fairfax County, has been relieved of duty after five years on the force, said Lucy Caldwell, a Fairfax County police spokeswoman.
The victim, a 42-year-old Manassas woman, reported to police that Summers sexually assaulted her between September 1 and October 31 of 2009 in her home, Prince William County police said.
At the time, Summers and the victim were involved in a relationship, police said.
Summers is being held without bond, police said, and online court records do not indicate whether he has an attorney. He is scheduled to appear in court on July 18.