A surveillance company is developing SignalTrace technology that adds sensors to automatic license plate readers (ALPRs) to capture Bluetooth identifiers from phones, AirPods, and smartwatches in passing vehicles. The system would let law enforcement potentially identify specific drivers or passengers, not just track license plates.

ALPR cameras already blanket the U.S., deployed by police departments and private entities nationwide. SignalTrace expands their scope significantly, transforming these roadside devices from vehicle trackers into people trackers by harvesting unique device fingerprints alongside plate data.

The technology raises immediate privacy concerns given ALPRs' widespread deployment and existing data collection practices. Law enforcement agencies could build detailed movement profiles of individuals without traditional identification methods, creating persistent tracking capabilities across multiple data sources.

This represents a significant escalation in surveillance infrastructure, moving from public vehicle monitoring to personal device harvesting. The integration of consumer electronics identifiers into law enforcement tracking systems fundamentally shifts the privacy calculus for anyone carrying a Bluetooth-enabled device on public roads.