As automatic license plate reading cameras placed on street corners and public spaces in the US spread as a crime-fighting tool, they have sparked a serious debate over privacy and constitutional rights. These systems record the license plate and distinguishing features of every passing vehicle, creating a massive database.
Expanding surveillance network
These small solar-powered cameras photograph each vehicle's license plate, model, color, and even details like bumper stickers, creating a 'vehicle fingerprint.' Flock Safety, a leading company in the sector, says it conducts billions of vehicle scans per month. According to ACLU estimates, there are between 80,000 and 100,000 Flock cameras in the country. The company states it works with over 6,000 communities, more than 5,000 law enforcement agencies, and over 1,000 businesses.
Privacy violations and false accusations
Privacy advocates like the Electronic Frontier Foundation (EFF) emphasize that the real problem is not a single photo but the searchable data archive that accumulates over time and can be shared across jurisdictions. They warn that such an archive could create a mosaic of a person's life, revealing movements, relationships, and routines.
The EFF found searches linked to protest activities in Flock's audit logs. Cases have also been reported where drivers were stopped at gunpoint due to misreads. In Colorado, a woman was charged with porch theft after her vehicle was mistakenly linked to a crime scene based on surveillance technology, including Flock cameras.
Law enforcement, however, argues that a license plate is public information, that officers see what anyone can see, and that this technology greatly speeds up investigations. Flock says it imposes strict limits on data retention periods, highlights user accounts and audit logs, and claims its systems support over one million investigations a year.
Federal courts' approach
In March 2026, the Fifth Circuit Court of Appeals issued a significant ruling in United States v. Elijah Porter. The court held that an ALPR system consisting of about ten cameras provided only periodic information about a person's movements, which was far more limited than geofence data or cellphone location data, and therefore did not constitute a search under the Fourth Amendment.
In the case of Schmidt v. City of Norfolk, concerning a system with 176 cameras and a 21-day footage retention period in Norfolk, Virginia, a federal judge granted summary judgment in favor of the city. However, the judge warned that ALPR technology could become so intrusive at some point that it crosses constitutional privacy boundaries. The case is currently before the Fourth Circuit Court of Appeals.
The Supreme Court's ruling last month in Chatrie v. United States, which held that police obtaining a person's Google Location History constitutes a search, bolstered critics' claim that the searchable archive of past movements is constitutionally distinct. However, while cell phones provide continuous tracking, ALPR cameras are typically placed at fixed locations.
Ban proposal from Congress
The debate has also reached Congress. Tennessee Republican Representative Tim Burchett introduced the 'Protection Against Mass Surveillance Act,' which would ban the federal government from purchasing or using mass tracking tools and prevent states from using federal funds for these systems. "We need to ban these damn things," Burchett said, arguing that these cameras are unauthorized surveillance tools that violate the Fourth Amendment.
