Virginia Code Title 46.2. Motor Vehicles § 46.2-834. Signals by law-enforcement officers, crossing guards, and flaggers

A. Law-enforcement officers may assume control of traffic at any intersection, regardless of whether such intersection is controlled by lights, controlled by other traffic control devices, or uncontrolled. Whenever any law-enforcement officer so assumes control of traffic, all drivers of vehicles shall obey his signals.

B. Law-enforcement officers and uniformed school crossing guards may assume control of traffic otherwise controlled by lights, and in such event, signals by such officers and uniformed crossing guards shall take precedence over such traffic control devices.

C. Uniformed school crossing guards may control traffic at any marked school crossing, whether such crossing is at an intersection or another location. Uniformed school crossing guards who are supplied by their local school division with hand-held stop signs shall use such signs whenever controlling traffic as authorized in this subsection.

D. Whenever an authorized flagger assumes control of vehicular traffic into or through a temporary traffic control zone using hand-signaling devices or an automated flagger assistance device, all drivers of vehicles shall obey his signals.