License Plate Reader Historical Searches Should Require a Warrant
Original: License plate reader searches should require a warrant
Why This Matters
As ALPR cameras proliferate, the legal framework governing their use will shape both law enforcement capabilities and civil liberties nationwide.
Criminologist Andrew Wheeler argues that historical searches of automated license plate reader (ALPR) data should require a warrant, citing the Norfolk, VA case Schmidt v City of Norfolk and Supreme Court precedent in Carpenter v US, warning that ubiquitous cameras will inevitably trigger constitutional scrutiny.
Andrew Wheeler, a criminologist and data scientist who works with police departments, published a detailed argument that historical searches of ALPR (automated license plate reader) data should require a warrant. He served as an expert witness for the Institute for Justice in Schmidt v City of Norfolk, a Virginia case challenging whether searching cached ALPR data constitutes an illegal search. The judge ruled against plaintiffs but notably wrote the surveillance was 'not today' too intrusive — implying a threshold exists.
Wheeler draws on Carpenter v US, in which the Supreme Court ruled police must obtain a warrant for cell-site location information (CSLI) from carriers, finding the comprehensive tracking capability violated reasonable privacy expectations. He also references Chatrie (geofence warrants) and Beautiful Struggle v Baltimore as related precedent.
Wheeler distinguishes between active flags — alerting police when a stolen car passes a camera — and historical searches covering a vehicle's movements over days or weeks. He argues requiring warrants for historical queries would not significantly hinder investigations. He further warns that the current status quo, in which many agencies do not retain ALPR data to avoid legal exposure, is counterproductive: it prevents both illegal searches and legitimate investigative use. He calls current abuse-prevention standards 'laughable' and recommends states enact statutory warrant requirements proactively.