Denver auditor refuses to sign city's current contract with Flock Group: "I just want that data secure"

Denver Auditor Tim O'Brien is refusing to sign the city's current contract with Flock Group, the company behind Denver's network of more than 100 license plate-reading cameras, citing what he says are significant risks to residents' privacy and potential liability for the city. His decision comes as other city officials continue to defend the technology and maintain that the agreement is valid and properly vetted.

"I think personally identifiable information is something that needs to be protected," said O'Brien.

O'Brien told CBS Colorado that documents provided to his office during his review -- including after the mayor's contract extension and recent provisions added to the program -- show a significant amount of users accessing Denver's Flock data are outside the Denver Department of Public Safety.

"One of the more persuasive things to me was they sent me information on who has accessed Flock data under the city contract and 80% of those that have access are outside the Department of Public Safety," he said. "Information is accessed by municipal police departments around the state of Colorado, the state patrol and other agencies. I don't know what's happening to that data when it gets down to a municipality and neither does the Department of Safety."

The auditor's concerns were outlined in a letter sent earlier this week to Denver Police Chief Ron Thomas, Mayor Mike Johnston and all 13 city council members. In that letter, O'Brien wrote that the contract "incurs a risk of liability for the city," pointing specifically to the potential for PII collected through Flock surveillance to be shared with agencies outside Denver, which he argues conflicts with the city's written agreement with the company.

"I just want that data secure, so that you and I as citizens don't have our data being exposed to people that shouldn't have it," he said.

The mayor's office pushed back on Wednesday, telling CBS Colorado the contract is already in effect and was properly vetted. The full statement reads:

The contract became effective upon the mayor's signature. However, the auditor is still required by City Charter to countersign the contract. To be clear, the auditor's role is to determine whether the city has obtained proper approvals, completed necessary paperwork, and ensured there is enough money in the budget to carry out a contract, all of which has been done. The responsibility of providing legal analysis is carried by the City Attorney's Office, which thoroughly vetted this contract and confirmed there is no lawful basis for the Auditor to withhold his signature.

O'Brien disputes that interpretation of his authority.

"I think the charter tells me that I can withhold my signature if I think it creates a liability for the city, and that's exactly what I say in that letter," he said.

The auditor also said his review was hindered by delays and a lack of transparency from multiple city departments. He told CBS Colorado that many documents arrived "highly redacted."

"I find that against the law also, because the auditor, by city charter, really has unfettered access to any and all information kept by city government," O'Brien said.

He said the information he received raised additional questions and ultimately solidified his decision to withhold his signature. While Denver police have credited Flock cameras with helping recover stolen vehicles and solve violent crimes, O'Brien said the broader policy debate remains unresolved.

"Do we want mass surveillance, or do we want to fight crime?" he said. "I think we want to fight crime, but in doing that, are we mass surveilling the citizens of Denver? That's the issue that needs to be worked out before they contract with anybody."

The city's existing agreement with Flock expires at the end of March. The mayor's office has already begun accepting bids from other license‑plate reader providers, while some city council members continue to express concerns about privacy, data‑sharing and long-term oversight.