When a Camera Becomes a Dragnet: the Fourth Amendment problem with automated license plate readers.
There is a good chance a camera on a pole near you is reading every license plate that passes. It records the plate, the make, the color, the time, and the location, then uploads all of it to a searchable database that other agencies can query. Flock Safety, the company behind much of this infrastructure, says it serves more than 12,000 clients, including over 5,000 law enforcement agencies.
The legal defense of this technology rests on a simple analogy. A fixed camera reading a plate, the argument goes, is no different from a police officer standing on a corner writing that same plate in a notebook. Both observe a vehicle in public, where no one has a reasonable expectation of privacy. Courts have started to accept that framing. In State v. Simonson, decided in January 2026, a Washington appeals court held that a license plate image captured on a public road is equivalent to an officer manually noting a plate and carries no Fourth Amendment protection. A federal court reached a similar result in Schmidt v. City of Norfolk, granting summary judgment to the city and pointing to the limited number of cameras, short retention periods, and the absence of continuous monitoring.
I think the analogy is wrong. And the reason it is wrong is technical, not partisan.
One officer is not ten thousand cameras
An officer noting a plate is a single observation, bounded by where that officer happens to be and how long they care to watch. A networked camera system is none of those things. It is persistent, automated, and connected. It does not note one plate. It notes every plate, continuously, and it keeps the record. String enough of those observations together and you no longer have a snapshot. You have a map of where a person goes, when, and how often.
The Supreme Court has already drawn this line. In Carpenter v. United States (2018), the Court held that accessing historical cell-site location data is a search precisely because aggregated location records reveal what it called the privacies of life in a way a single data point never could. Six years earlier, in United States v. Jones (2012), Justice Sotomayor warned that comprehensive tracking produces a precise, encyclopedic record of a person's movements. The notebook analogy holds only if you ignore scale, and scale is the entire purpose of the technology. A system designed to watch everyone, all the time, is not a single officer with a pen.
The data does not stay where it was collected
The privacy concern is not hypothetical. A class action filed in San Francisco Superior Court in February 2026 alleges that Flock violated California's ALPR Privacy Act by sharing license plate data with out-of-state and federal agencies, a practice the 2015 statute was written to prevent. According to that suit, federal agencies including ICE, CBP, the FBI, and ATF queried the San Francisco Police Department's camera database more than 1.6 million times. In a separate case, the city of Mountain View terminated its Flock contract after roughly 600,000 unauthorized searches. Data collected for local policing in California did not stay local, and in many cases the cities that owned the cameras did not know who was running searches through them.
Communities are already pulling out
This is not a fringe reaction. Between August 2021 and May 2026, 82 Flock contracts were terminated across 28 states, according to reporting by the San Francisco Standard. Washington went further and passed a Driver Privacy Act in 2026 that requires warrants for most sharing of license plate data with federal agencies. These are local governments deciding, after the fact, that the trade they made was worse than the problem it was supposed to solve.
If you run cameras yourself, this is your problem too
This is not only a government issue. If your business operates plate readers in a parking lot, a gated community, or a retail property, the same legal exposure can apply to you. California courts have held there is no exemption for small operators, and a growing wave of suits now targets private property owners, not just the manufacturer. If you collect this data, you should know exactly what you are capturing, how long you keep it, who can access it, and what your disclosure obligations are.
The bottom line
The Fourth Amendment was written to prevent general, surveillance-without-suspicion of ordinary people going about their lives. A single officer with a notebook was never the threat it was built to guard against. A private company logging the movements of an entire country, one plate at a time, and selling access to whoever asks, is much closer to that threat. The courts will spend the next few years sorting out the doctrine. The technology is not waiting for them, and neither should the rest of us.