Maine License Plate Reader (ALPR) Laws (2026)

Maine has a short, specific ALPR statute, 29-A M.R.S. § 2117-A, and it starts from a ban. In one sentence, "a person may not use an automated license plate recognition system" except as the statute allows, and the exceptions cover the Department of Transportation, State Police commercial-vehicle screening, and law enforcement agencies, with retained data limited to 21 days in most cases and treated as confidential.

Information reviewed September 30, 2026.

For related pages, see the Maine entry in the state comparison, the ALPR laws hub, Are Flock cameras legal?, What are Flock cameras?, and our Maine surveillance camera laws guide.

What does Maine's statute prohibit, and who is excepted?

Subsection 2 of § 2117-A provides: "Except as otherwise provided in subsection 3, a person may not use an automated license plate recognition system." Subsection 3 lists the exceptions:

• the Department of Transportation, for protecting public safety and transportation infrastructure;
• the State Police Bureau, for commercial motor vehicle screening and inspection; and
• any state, county, or municipal law enforcement agency, when providing public safety, conducting criminal investigations, and ensuring compliance with local, state, and federal laws.

The definition excludes photo-monitoring systems that the Maine Turnpike Authority or law enforcement uses for toll enforcement. The statute's history shows only two enactments, PL 2009, c. 605 (new) and PL 2013, c. 267 (amended).

What information may a law enforcement system use?

Under subsection 3(C), a law enforcement agency's system may use only information entered by a law enforcement officer "based on specific and articulable facts of a concern for safety, wrongdoing or a criminal investigation," or entered pursuant to a civil order. It may also use records from the National Crime Information Center database or an official published law enforcement bulletin. An authorized user may use the system only for the official and legitimate purposes of the user's employer.

How long can the data be kept?

Under subsection 5, data collected or retained under subsection 3 that is not intelligence and investigative record information, as defined in 16 M.R.S. § 803(7), and is not commercial-vehicle screening data "may not be stored for more than 21 days." The 21-day limit dates to the original 2009 enactment (PL 2009, c. 605); PL 2013, c. 267, Part B, § 23 updated the subsection's cross-reference to the Title 16 definition.

The 21-day limit is written for data that is not intelligence and investigative record information. Section 2117-A sets no storage limit for data that qualifies as intelligence and investigative record information.

Is the data public?

No, with narrow exceptions. Under subsection 4, data collected or retained under the statute are "confidential under Title 1, chapter 13 and are available for use only by a law enforcement agency in carrying out its functions." Title 1, chapter 13 is the Freedom of Access Act. The data is also available to an agency collecting information under subsection 3 for its intended purpose and in any related civil or criminal proceeding. Agencies may release aggregate summary reports that do not reveal individual activity and may share commercial-vehicle screening data with the Federal Motor Carrier Safety Administration.

What is the penalty?

Subsection 6 provides that "[v]iolation of this section is a Class E crime."

Does the statute reach private parking lots?

A separate 2025 statute on parking enforcement at property accessible to the public, 10 M.R.S. § 1500-LL, cross-refers to the ALPR statute. Subsection 3 states that "[t]he provisions of Title 29-A, section 2117-A prohibit the use of an automated license plate recognition system at a property accessible to the public for the parking of motor vehicles," subject to the exceptions in that section. A violation of § 1500-LL is a violation of the Maine Unfair Trade Practices Act, with treble damages on improperly assessed fines (PL 2025, c. 350, § 1). The effective date of chapter 350 was not checked.

Have Maine courts addressed the statute?

No Maine decision interpreting § 2117-A was found. State v. Norris, 2023 ME 60, mentions a special agent running the defendant's vehicle through three New England plate readers as part of a probable-cause showing for a tracking warrant. The opinion does not address § 2117-A or whether ALPR use is a search. The court treated the plate-reader data as corroboration of the informants' reports about the defendant's out-of-state travel, and listed it among the information that would support probable cause for the later search warrant.

What local records exist?

The records below come from the sources named, with the dates those sources give. The list is not complete and a status can change.

• South Portland: the police department's program is recorded as ended as of June 22, 2026, according to a city news release.
• Lewiston: the police department's program is recorded as active as of August 16, 2026, according to a Sun Journal report.

Has the law changed recently?

The statute pages reviewed on September 30, 2026 state "Data for this page extracted on 10/20/2025." A public law from the 2026 legislative session that amended § 2117-A would post after that extraction. The Legislature's digests of laws enacted in its 2025 and 2026 sessions (the 2026 session adjourned April 29, 2026) list no law amending § 2117-A. No 2026 bill or court decision applying § 2117-A was verified either. Check the current statute text on the Legislature's site before relying on any detail here.

How can you check a local system?

Because the statute is a general ban with exceptions, the useful questions are whether the operator falls within an exception and how long it keeps data. Ask the police department or town for its written policy and its retention setting, and compare the retention setting with the 21-day limit. Because the data is confidential, a request for individual plate records should not be expected to succeed, but agencies may release aggregate summary reports under subsection 4.

Frequently asked questions

Last updated: September 30, 2026. The statute text reviewed carried an extraction date of October 20, 2025; confirm current text before relying on it.

A separate law limits sharing with immigration authorities without naming plate readers. Public Law 2025, chapter 517 (L.D. 1971), which became law without the Governor's signature on January 11, 2026, enacts 5 M.R.S. § 4763. It provides that a law enforcement agency may not "use agency or department money or personnel to investigate, interrogate, detain, detect, stop, arrest or search a person for immigration enforcement purposes," including "[p]roviding to immigration authorities personal information about the person, including the person's home address or work address," subject to listed exceptions such as joint task forces whose primary purpose is not immigration enforcement, and it does not bar exchanging immigration status information under federal law. The chapter has no emergency clause, and the Revisor of Statutes publishes it with the laws of the Second Regular Session, whose general effective date for nonemergency laws is July 29, 2026. The law does not define personal information or mention plate data, and this page does not decide how it applies to plate reader records.

Toll images are covered by a different statute. Under 23 M.R.S. § 1980(2-B)(B), a photograph, videotape, or other recorded image prepared for enforcement of Maine Turnpike Authority tolls "is for the exclusive use of the authority in the discharge of its duties" and "is confidential and is not available to the public." The same paragraph says "[t]he authority shall make this information available to a law enforcement officer upon request" and may share it with other toll agencies. It sets no retention period.

Frequently Asked Questions

Does Maine have an ALPR law?

Yes. Title 29-A section 2117-A generally prohibits use of an automated license plate recognition system, with exceptions for the Department of Transportation, State Police commercial-vehicle screening, and law enforcement.

How long can Maine keep license plate reader data?

Data collected under subsection 3 that is not intelligence and investigative record information, and is not commercial-vehicle screening data, may not be stored for more than 21 days.

Is Maine plate reader data public?

No. It is confidential under the Freedom of Access Act, with exceptions such as aggregate summary reports that do not reveal individual activity.

What is the penalty for violating the statute?

A violation of section 2117-A is a Class E crime.

Can a private parking lot use a plate reader in Maine?

A separate 2025 statute states that section 2117-A prohibits use of an ALPR system at property accessible to the public for parking motor vehicles, subject to its exceptions.