ALPR (Automatic License Plate Reader)

An Automatic License Plate Reader (ALPR) is a camera-based system — mounted on enforcement vehicles, stationary poles, or overhead gantries — that uses optical character recognition to capture license plate numbers from passing traffic and immediately check them against databases of scofflaws, warrants, registration holds, and stolen vehicles. Match results are returned to enforcement officers in seconds, dramatically accelerating the pace of mass enforcement.

In NYC, ALPRs are used extensively by NYC marshals and sheriffs to identify vehicles eligible for booting at the $350 unpaid-violation threshold, by NYPD for stolen vehicle and warrant detection, and by DOT for commercial vehicle and bus-lane enforcement. ALPR-equipped marshal vehicles can sweep a block in minutes, flagging every scofflaw plate for immediate boot. This is why a vehicle's boot exposure depends less on where it parks than on whether any marshal ALPR has scanned it recently.

For fleet operators, ALPR is the reason boot thresholds matter so intensely. Once a fleet vehicle crosses the $350 line, every moment on a public street is a potential ALPR hit. Clear Plates helps fleets stay below the threshold by tracking unpaid balances per vehicle and alerting managers before the ALPR net closes in.