There are more than 1,000 automated license plate readers — many of them supplied by the tech company Flock Safety — that collect information about drivers' movements in the St. Louis region.
"I'm shocked at how there are so many of them now, [and] we didn't really know it was happening," said St. Louis resident Maria Ashby. " It was like we blinked and they were here, and all across America, all at once."
A growing number of community members have concerns about the cameras, and the effort to regulate and restrict the technology's use comes from both sides of the political aisle.
"I have been fascinated by how bipartisan this issue has been, particularly in a country that is so deeply divided," said University City resident Al Schad, who runs DeFlock U City. "It's really quite a depth and breadth of people that take issue with this, for a lot of different reasons."
Missouri is one of 20 states with little to no oversight of automatic license plate readers, also known as ALPRs. In 2025, a Republican state lawmaker sponsored legislation to prohibit the use of the cameras along roadways, but the bill didn't get far.
Rep. Raychel Proudie, D-Ferguson, said she wants to bolster penalties for police officers who misuse Flock cameras during next year's legislative session. She discussed the issue on "Politically Speaking" shortly after a Brentwood officer was accused of using license plate readers to track his ex-wife and as similar stories emerge across the country.
Hazelwood has had automated license plate readers since 2011. Its contract with Flock Safety began in 2023. Hazelwood Police Lt. Shane Parrish said the cameras have been useful in solving crimes including illegal dumping, vehicle theft, missing person cases and homicides.
"Before, [we] would be out there on the streets, knocking on doors, trying to locate a witness who observed the crime, looking for surveillance systems from businesses who might have caught a vehicle in the area. With Flock, we now have, hopefully, a license plate that we're able to identify, or some kind of identifying marks [that make it] a little bit easier to help us develop these leads," he said. "It's a tremendous help."
The department has access to 10 Flock cameras budgeted for the city, as well as two cameras from homeowners associations and another from a private business with a Flock contract.
"I receive calls quite frequently from people who are not happy and feel that it's a violation of their rights," Parrish said. "But then I have victims of crime, or their families, who are ecstatic that we were able to develop that lead that led to the apprehension of a criminal."
Parrish added that the department conducts monthly audits to ensure that the technology is not being misused.
ALPRs are not new, but security companies' use of artificial intelligence has brought the debate over privacy rights to a head, said Washington University law professor Neil Richards.
"AI can do surveillance at scale, and just as AI can read the make and model and distinguish characteristic dents and stickers and bumper stickers on a car, it can also be used for facial recognition," he said. "That's something American law has really failed to come to terms with. That's the really scary future technology, and it wouldn't be all that difficult to add facial recognition to Flock cameras."
Richards added that "American privacy law lags massively behind the rest of the world." He would like to see a general statute that limits surveillance technology and requires a warrant before it can be used — similar to the Wiretap Act of 1968, which made it a crime for police to monitor communications without a warrant while providing procedures for the police to get evidence on a case against a specific subject.
ALPR systems that use artificial intelligence allow public and private entities to track every vehicle user. That's a problem, according to Edward McPherson, a Washington University professor who recently wrote a book about mapping and surveillance over the past few centuries.
"You might modify your behavior. You might not do lawful things because you think you might get incorrectly swept up in a dragnet. Like, 'I won't go hear her speak, even though I have every right to, because I might show up on someone's list,' or, 'I might not go to that house of worship,' or 'I might not go to that neighborhood,'" McPherson said. "We start to internalize our own oppression and don't do things that we have the right to do because we're worried about showing up and being incorrectly targeted."
To learn more about surveillance technology— and the movement to limit or ban its use in St. Louis — listen to "St. Louis on the Air" on Apple Podcasts, Spotify, YouTube or click the play button below.
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