They are being supported by dog handlers and officers with access to Automatic Number Plate Recognition (ANPR) technology.

BBC: Armed officers in Marsh Farm, Luton

We could start the transition today, using existing low-cost all-electronic tolling (transponders and license-plate imaging) on all limited-access highways, such as Interstates and expressways.

WSJ: Is Raising the U.S. Gasoline Tax the Best Way to Pay for Highways?