Leonardo's SignalTrace blends phone signals with license-plate data to track vehicles and people

Leonardo's SignalTrace captures Bluetooth, RFID and other broadcast signals from consumer devices and cross-references them with automatic license-plate reader records to build electronic fingerprints of recurring vehicle-device pairings. The company asserts the tool only gathers anonymous signatures, requiring traditional investigative steps to attach names. Critics argue that linking a device to a known car or repeated proximity to other tracked devices can effectively identify owners, even without a direct name.

Pilot deployments have been reported in Oxon Hill, Maryland, and the technology is listed on a New York state procurement sheet. Federal privacy guidance defines personally identifiable information broadly, and recent Supreme Court rulings on phone-location data suggest such pattern-based surveillance may constitute a search. The debate centers on whether indirect association through SignalTrace warrants the same constitutional protections as direct location records.