Flock is an Automated License Plate Recognition (ALPR) system that uses cameras to automatically read government issued license plates. The cameras capture the license plate number, along with the vehicle's make, model, and color. The system does not use facial recognition and does not provide or store personal identifying information like names, addresses, or dates of birth of anyone associated with the license plate.
Flock Safety
The Boulder Police Department uses Flock Safety's Automated License Plate Recognition (ALPR) technology as a vital tool to protect our community and solve crimes. This system reads license plates on public roads to help us find stolen vehicles, missing people, respond to Amber Alerts, and investigate crimes. Since implementing Flock, we have achieved a 34.5% reduction in motor vehicle thefts and successfully solved numerous serious crimes, from hit-and-run crashes to violent attacks.

As with any technology, how it is used is important. We are committed to using this technology responsibly and transparently, with strict safeguards in place to ensure it serves only legitimate law enforcement purposes while respecting our community's values and privacy. Flock does not store any name, address, or date of birth of individuals. Data is only maintained for 30 days. In addition, our department now prevents non-Colorado agencies from using the national look-up feature in this system.
We understand that individuals may be more interested in how we are using this tool given enforcement trends nationally. As a reminder, the Boulder Police Department does not participate in immigration enforcement.
For more information, view our FAQ below.
License plate data is retained for 30 days, after which it is automatically deleted from the system.
The Boulder Police Department uses Flock solely for legitimate law enforcement purposes, including criminal investigations, finding missing or endangered persons, Amber Alerts, and tracking stolen vehicles. Officers must have a clear justification for any search they run.
On a limited basis, yes. Like other criminal justice records, we share our Flock data with other law enforcement agencies and some of them share their data with us. All requests to share access to our data must be approved by a supervisor, logged, and tracked through strict audit trails. Earlier this year, the Boulder Police Department made a decision to only share data with Colorado law enforcement agencies. As of June 2025, we deactivated the "national lookup" feature, so out-of-state agencies can no longer search our system for specific, identified license plate numbers. This restriction was put in place to ensure that the agencies we share with are governed by the same laws we are. A complete and up-to-date list of the agencies Boulder PD shares data with can be found on our Flock Transparency Portal. Boulder Police Department does not have any agreement with U.S. Border Patrol for Flock searches.
While the data is stored on Flock's servers, the Boulder Police Department retains the ability to determine who has access to our data. Aside from other law enforcement agencies we have agreed to share our data with, Boulder Flock data is never shared or sold to other third parties. Each user must have a unique login, and there is a complete audit trail of all searches conducted in the system.
Multiple safeguards protect against misuse: supervisory approval is required for external data sharing and all searches are logged. The company has recently introduced additional safeguards to prevent and automatically block searches for reasons that violate Colorado law and/or department’s internal policies and commitment to the Boulder community, such as searches for reasons relating to immigration.
Since implementing Flock, Boulder has seen a 34.5% reduction in motor vehicle thefts compared to the five-year average. The system has been instrumental in solving serious crimes, including helping to quickly locate the suspect vehicle in the June 1 antisemitic terror attack, and assisting with investigations involving mail fraud, felony menacing, assault, hit-and-run crashes, and homicide cases. Flock has been helpful in our response to and investigation of nearly every major crime that BPD has investigated since its implementation.
Boulder Police Department selected Flock Safety based on the company's strong commitment to transparency and public safety. Flock provides comprehensive transparency tools, including public portals that allow community members to view usage data and understand how the system operates. The company has also been responsive to law enforcement and community concerns, continuously updating its technology with additional safeguards to prevent misuse.
Flock's focus on legitimate law enforcement purposes, combined with their willingness to implement features like automatic blocking of immigration-related searches and enhanced audit controls, aligns with Boulder's commitment to responsible policing and community values.
All agencies who enter agreements with Flock are subject to their terms when conducting searches. You can learn more here: https://www.flocksafety.com/legal/terms-and-conditions
Specifically, permitted reasons for searching Flock data are defined in these terms and conditions as "legitimate public safety and/or business purpose, including but not limited to the awareness, prevention, and prosecution of crime; investigations; and prevention of commercial harm, to the extent permitted by law."