The Denver Police Department wants hundreds of thousands of dollars to continue a program that scans license plates on local roads with a tech company’s solar-powered cameras.
The department argues that the camera network has helped police find suspects and stolen cars during its one-year pilot phase, leading to hundreds of arrests.
But critics say the program is Orwellian, violates Fourth Amendment rights and could be used by President Donald Trump’s administration to attack political opponents and dissent.
Now, the Denver Police Department is asking Denver
City Council for $666,000 to operate the cameras for another two years.
The Safety, Housing, Education and Homelessness Committee passed the item on to the full council for a vote. The city has already spent about $350,000 on the pilot phase.
Denver police say the program helps curb crime.
Denver’s auto theft numbers dropped during the Flock pilot.
In 2022, the city saw an all-time high of almost 15,000 auto thefts. In 2024, there were about 8,500 thefts. That mirrors a national drop in vehicle thefts, though Denver’s drop outpaced many other cities.
Still, the city’s car theft numbers are far higher than the average in cities of comparable size.
The year-long pilot program led to 289 arrests, 170 recovered vehicles and 29 recovered firearms, the department reported. The cameras helped stop a robbery scheme, in real-time, in Montbello, and two burglaries in Cherry Creek, and helped to locate suspects in a “Kia Crew” theft ring, police said.
Flock faces legal challenges elsewhere.
Flock’s presence in Norfolk, Va., has faced legal challenges in federal court from the Institute for Justice, which argued residents’ Fourth Amendment rights are violated by the cameras.
“These cameras can track people’s every move over a prolonged time period,” Institute for Justice attorney Michael Soyfer said in a statement. “If the government wants to do that, it should have to get a warrant.”
The city of Norfolk tried to get the lawsuit dismissed, but a judge rejected the attempt, citing Carpenter v. United States, a case that banned using cell phone location data to track movement.
“A reasonable person could believe that society’s expectations, as laid out by the Court in Carpenter, are being violated by the Norfolk Flock system,” Chief Judge Mark Davis wrote.
The case against Norfolk is ongoing.
The American Civil Liberties Union describes the Flock system as “mass surveillance” and “dangerously powerful and unregulated.”
The ACLU urges communities to oppose Flock systems “full-stop,” saying the company is building a giant camera network tracking people’s movements nationwide.
“Every new customer that buys and installs the company’s cameras extends Flock’s network, contributing to the creation of a centralized mass surveillance system of Orwellian scope,” the ACLU wrote.
The ACLU is not fully opposed to Flock working with departments to use the system to check license plates against stolen vehicle lists, which is the primary function in Denver. But Denver also collaborates with other law enforcement agencies with the data – a greater concern for the ACLU.
How license plate readers work in Denver
Flock’s solar-powered cameras capture license plate numbers and let police know, in real time, where stolen vehicles are located.
The license plate readers do not take photos of drivers or passengers and do not use facial recognition software. The race and gender of drivers is not tracked. The system also has weaknesses: It can be stymied by certain license plate covers.
The license plate readers are not used for traffic or immigration enforcement, according to Flock.
The readers do track hot lists from city, state and federal agencies for stolen and wanted vehicles and vehicles tied to missing persons.
The data is stored for 30 days – the same retention period as the city’s HALO surveillance cameras. The public does not have access to the data, unless the information is part of certain criminal investigations and subject to the Colorado Criminal Justice Records Act.
Flock does not have access to the state Division of Motor Vehicle’s records.
The data can only be used by law enforcement agencies in criminal investigations. All search records are retained indefinitely to assist in future investigations, and the system keeps permanent records of how the database is used..
Currently, the city has 111 cameras stationed at 70 sites around Denver. Cameras have detected more than 2 million vehicles in the past 30 days, connected with more than 75,000 hot list hits and leading to more than 3,100 searches for vehicles.
A DPD audit showed no instances of the license plate readers being abused or misused.
Still, the department says it needs to do better. In roughly 17 percent of searches of the system, officers failed to include case numbers. The department plans a refresher course on how the data can be used.
Who uses these systems?
More than 80 agencies, from county sheriff departments to city police departments, use Flock systems across the state.
Nationwide, about two-thirds of cities Denver’s size use Flock.
The data helps metro law enforcement agencies and the Metro Auto Theft Task Force work together in identifying car-theft rings.
Investigations are triggered by both local, state and federal government agency databases. The “hot lists” that the system monitors come from sources including the National Center for Missing and Exploited Children Amber Alert program, the U.S. Department of Justice’s National Crime and Information Center Missing and Unidentified Persons System, and the Colorado Crime Information Center.
Denver police also say they work with the Bureau of Alcohol, Tobacco, Firearms and Explosives and postal inspectors who investigate mail theft on sharing data for investigations.
Flock does not currently contract with Immigration and Customs Enforcement or Homeland Security, according to Denver Police.
Agencies that want to use Denver data must agree not to give information to ICE or use it for civil violations related to immigration.
How council members responded
At the committee hearing, Councilmembers Kevin Flynn and Sarah Parady raised questions about the Fourth Amendment implications of the technology.
While there are limits on how information can be shared with federal law enforcement, Parady raised the concern that federal agencies are collaborating with each other in support of ICE investigations.
“I don't know that we can trust federal law enforcement agencies to make a data request and properly identify the purposes that it's being used for,” she said.
She worries that the information could be used by agencies outside the rules DPD has established.
“The entire Department of Justice right now is basically being geared towards repression of dissent, you know, punishment of presidential enemies, and gearing up the deportation machine,” she said. “So that's my concern about this. It’s not a DPD concern, but just a concern that we're creating some serious potential for unintended consequences by using the tech.”
“I think it’s a valid concern,” DPD Commander Jacob Herrera responded.
Local police, he said, have to trust their relationship with federal law enforcement and hope agencies keep their word.
