The Prince William County prosecutor, responding to a request from a state delegate and a county supervisor has asked the Virginia State Police to investigate whether the two acted improperly during the search for a site for a new county government building.

Del. David G. Brickley and Supervisor G. Richard Pfitzner, both leading Democrats in the suburban county, requested the inquiry Tuesday in order to clear their names, Pfitzner said. A real estate firm owned by Brickley, Pfitzner and a third partner actively pursued business deals in the neighborhood of what became the county's chosen site while the supervisors were discussing the site selection in closed meetings.

Prince William Commonwealth's Attorney Paul B. Ebert said yesterday the state police would conduct the investigation after it receives a go-ahead from the Virginia state attorney general. He said the inquiry would focus on possible violations of the state conflict-of-interest law.

Virginia law allows county boards to meet in private to discuss land purchases. State law, however, forbids officials from improperly sharing or profiting from confidential government information.

The county chose the 142-acre Davis property in eastern Prince William earlier this month for its governmental complex, with Pfitzner abstaining from the final vote. While that site was under consideration in private meetings last summer, the real estate firm was brokering the purchase of a nearby 16-acre property, negotiating for an adjacent 50-acre parcel and asking dozens of owners near the site if they would sell their land.

Pfitzner and Brickley have said they did nothing improper and never discussed where the county complex would go. "My personal integrity in both public service and business has been a most treasured asset unquestioned until this episode," Pfitzner and Brickley wrote in separate, identical letters to Ebert on Tuesday. "I choose not to be tried by rumor, innuendo and what the press chooses to print, but must demand an inquiry by the proper authorities."