With a badge on his chest and a gun on his hip, Youlen gave the driver a stern warning to stay off the road.

The stop was routine police work, except for one fact: Youlen is not a Manassas officer. The citation came courtesy of the private force he created that, until recently, he called the "Manassas Junction Police Department."

He is its chief and sole officer. 

He is a force of one.

And he is not alone. Like more and more Virginians, Youlen gained his police powers using a little-known provision of state law that allows private citizens to petition the courts for the authority to carry a gun, display a badge and make arrests. The number of "special conservators of the peace" — or SCOPs, as they are known — has doubled in Virginia over the past decade to roughly 750, according to state records.