Colorado License Plate Reader Laws

Status at a glance

No ALPR statute

We didn’t find a Colorado statute that specifically regulates license plate readers. A full-text search of the 2024 Colorado Revised Statutes titles on criminal procedure, government records and vehicles found no use of the terms plate reader or plate recognition. Three items are sometimes mentioned in this context. None is an ALPR statute.

• SB 26-070, “Ban Government Access Historical Location Information Database,” is listed on the General Assembly’s bill page with the status “Lost.” It isn’t law.
• SB 26-152 became law, but it addresses ALPRs only to exclude them (below).
• C.R.S. § 24-72-113 limits retention of “passive surveillance” records, but its text doesn’t mention license plate readers (below).

SB 26-152 excludes ALPRs

SB 26-152, “Changes Automated Vehicle Identification System Usage,” governs automated vehicle identification systems used for civil traffic enforcement. Its legislative declaration says: “This act does not regulate, limit, or otherwise affect the use of ALPR systems, and nothing in this act is intended to expand, restrict, or modify existing law governing ALPR systems.” The act also adds a definition stating that an automated vehicle identification system does not include automated license plate reader systems (new C.R.S. § 42-4-110.5(1.1)(a)(III)).

The passive surveillance law

Section 24-72-113 defines “passive surveillance” as a government entity’s use of cameras or other image recording devices to capture images of human activity “on a routine basis or for security or other purposes, including monitoring or recording traffic.” It provides: “All passive surveillance records must be destroyed after the third anniversary after the date of the creation of the passive surveillance record unless retention is authorized by this section” (§ 24-72-113(2)(a)). Access after the first anniversary is limited to listed situations.

The section doesn’t mention ALPRs. Whether ALPR data counts as “passive surveillance” is an open question we haven’t seen a court answer. This page doesn’t treat three years as a Colorado ALPR retention rule. See ALPR data retention and sharing.

The state constitution: People v. McKnight

In People v. McKnight, 2019 CO 36, decided May 20, 2019, the Colorado Supreme Court held that a sniff by a drug-detection dog trained to alert to marijuana is a search under the Colorado Constitution, because it can detect lawful activity. The court also concluded that “the appropriate remedy for this violation of the Colorado Constitution is the exclusion of the evidence at issue.” The case isn’t about ALPRs.

McKnight describes Colorado’s history of reading article II, section 7 more broadly than the Fourth Amendment. In Charnes v. DiGiacomo, the court “first charted its own course in interpreting article II, section 7 to afford broader protections than the Fourth Amendment.” Among the later cases it lists is People v. Oates (Colo. 1985), described as “holding that the installation and presence of a tracking device in purchased commercial goods constitutes a search under the Colorado Constitution.”

The court added a caveat about its own trend: “In decades past, our opinions demonstrated a willingness to interpret the state constitution to afford broader protections than its federal counterpart. Yet, in recent years, we have moved away from this interpretive independence” (¶ 28). How these cases would apply to ALPR data hasn’t been decided. See is ALPR a search? and the mosaic theory.

Agency policies: Clear Creek and Boulder

Without a statute, retention and sharing rules depend on each agency. Two examples show how much they can differ.

Clear Creek County Sheriff’s Office Policy 424 (Lexipol, dated 2026/02/10) is one agency’s policy:

• “Reasonable suspicion or probable cause is not necessary before using an ALPR.”
• A deputy must verify an ALPR response through the Colorado Bureau of Investigation “before taking enforcement action that is based solely upon an ALPR alert,” with an exception for exigent circumstances.
• “All ALPR data will be purged after 21 days” unless it is or may become evidence, or is subject to a lawful action to produce records.
• Data may be shared with local, state and some federal agencies. Releases to a federal agency should be only for a criminal investigation and only after notifying the County Attorney.

The City of Boulder’s Flock page describes the Boulder Police Department’s practice:

• “License plate data is retained for 14 days, after which it is automatically deleted from the system.”
• Boulder says it decided to share data only with Colorado law enforcement agencies and, as of June 2025, deactivated Flock’s national lookup feature, so “out-of-state agencies can no longer search our system for specific, identified license plate numbers.”
• “All requests to share access to our data must be approved by a supervisor, logged, and tracked through strict audit trails.”

Other Colorado agencies may follow different rules. See can police search Flock data from other states?

What this can mean in a Colorado case

• Which agency’s cameras captured the data, and what retention and sharing rules does that agency’s written policy set?
• Was the data still available under that agency’s retention period when it was requested? See requesting ALPR records in discovery.
• For a stop on an alert, was the alert verified as the agency’s policy requires?
• Did officers search stored location history over time, and does article II, section 7, as discussed in McKnight, bear on that search?
• Was the data obtained from another agency, including one outside Colorado, and under what sharing terms?