Free Guide to License Plate Reader Technology by State

Overview of License Plate Reader Technology Across the United States

License plate reader (LPR) technology, also called automatic license plate recognition (ALPR), uses high-speed cameras and software to read and record vehicle license plates. These systems capture images of plates, convert them to text, and store the information in databases. Law enforcement agencies, private companies, and government entities use this technology for various purposes including locating stolen vehicles, identifying suspects in crimes, and managing tolls on highways.

The technology has grown significantly since the 2000s. What started as a specialized tool used by a handful of agencies has expanded to thousands of police departments, traffic enforcement agencies, and private parking companies across all 50 states. A 2023 report indicated that over 70 percent of large police departments in the United States operate some form of LPR system. The data collected by these cameras can accumulate rapidly—some cities record tens of millions of plate reads annually.

Understanding how this technology works in your state requires knowing several factors: which agencies use it, what laws govern its use, how long data is kept, and what rules exist for sharing information. Different states have adopted vastly different approaches to regulating LPRs. Some states have strict privacy protections and transparency requirements, while others have minimal oversight. A few states have banned certain uses of the technology entirely.

The purpose of this guide is to explain how LPR technology operates in different states and what the current legal landscape looks like. This information can help you understand your state's policies, know what rights you may have regarding your data, and learn which agencies in your area use these systems. The guide focuses on factual information about existing regulations rather than predicting future changes.

Practical Takeaway: Before exploring state-specific information, understand that LPR regulations vary dramatically by location. Your state may have strong privacy rules, weak protections, or something in between. Learning your state's specific approach helps you understand what data collection may occur in your community.

How License Plate Readers Work and What Data They Collect

License plate readers use optical character recognition (OCR) technology to capture and interpret images of vehicle plates. The system photographs a vehicle's plate, extracts the characters and numbers, and converts this information into searchable data. Modern LPR cameras can read plates from moving vehicles at speeds up to 90 miles per hour, in various lighting conditions, and from multiple angles simultaneously. A single camera unit can process hundreds of plates per minute.

The data collected extends beyond just the plate number. Most LPR systems record the plate number, the date and time of the read, the location where the read occurred, and an image of the vehicle and plate. Some systems also capture the vehicle's color, make, model, and other physical characteristics. This collection happens continuously—whether or not law enforcement has any suspicion of wrongdoing. The camera does not distinguish between vehicles registered to people suspected of crimes and vehicles belonging to ordinary citizens.

A typical LPR setup includes one or more cameras mounted on police vehicles, fixed structures like utility poles or buildings, or placed in parking lots. Fixed systems can scan thousands of vehicles per day in a single location. Mobile units mounted on patrol cars scan plates as they drive through neighborhoods and along highways. Some agencies combine data from multiple readers to track vehicle movements over time and across geographic areas.

Data storage varies by system and agency. Some LPR data gets stored on local servers at the agency, while other systems use cloud-based storage provided by vendors. The databases can grow rapidly. For example, a major city's LPR system might collect and store 10 to 20 million plate reads in a single year. Over several years, these databases can contain hundreds of millions of records. This information becomes historical data that law enforcement can search to track where a vehicle has been.

Practical Takeaway: Every vehicle you drive can be photographed and recorded by LPR systems, regardless of whether you've committed any offense. Understanding what data is collected helps explain why privacy advocates and civil rights organizations have raised concerns about this technology in certain states.

State-by-State Regulations: Strong Privacy States

Some states have enacted laws that place meaningful restrictions on how law enforcement can use LPR technology and what happens to the data collected. These states generally require transparency about which agencies operate LPR systems, limit how long data can be stored, restrict who can access the information, and require documentation of why the technology is being used.

Vermont has some of the strongest LPR regulations in the nation. The state requires that agencies using LPRs maintain records of all LPR data, establish retention schedules (generally 10 years for unsolved criminal cases), and restrict access to law enforcement personnel working on legitimate investigations. Vermont law also requires annual reporting on LPR use. Citizens may request information about how LPRs operated in their area and what data was collected.

California has implemented detailed regulations under its 2015 Assembly Bill 1215. The law requires law enforcement agencies using LPRs to adopt written policies governing how the systems are used. Agencies must document their policies publicly. The rules specify that LPR data should only be used for legitimate law enforcement purposes. California requires agencies to delete LPR records after a certain period unless they relate to an active investigation or unsolved crime. Local communities in California can impose even stricter rules than the state minimum.

Connecticut requires that law enforcement agencies using LPRs establish written policies that include retention schedules, restrict data sharing, and authorize access only for legitimate law enforcement purposes. The state also requires agencies to report on their LPR activities. New Hampshire similarly mandates written policies and restricts how law enforcement can use the technology.

Louisiana requires that LPR data be deleted within 30 days unless it relates to a specific criminal investigation. This represents one of the shortest retention periods in the country. The state also limits which agencies can access the data and for what purposes.

Practical Takeaway: If you live in a state with strong LPR regulations, your state likely has laws limiting data storage time, restricting access to the information, and requiring transparency about how the technology is used. These states generally provide more privacy protections than the national baseline.

State-by-State Regulations: Moderate and Minimal Oversight States

Many states fall into a middle category where some regulations exist but oversight is less comprehensive than in the strongest privacy states. These states may have rules about certain LPR practices but lack detailed statewide standards. Instead, regulations may be set at the local or county level, or agencies may operate under general law enforcement guidelines rather than LPR-specific legislation.

Texas has no statewide LPR law governing how law enforcement uses the technology or how long data is stored. However, some individual police departments in Texas have adopted their own policies. For example, the Austin Police Department maintains a written LPR policy that addresses retention and use. But without statewide requirements, standards vary significantly across the state. Large departments may have detailed policies while smaller agencies have minimal oversight.

New York does not have comprehensive statewide LPR legislation. Law enforcement agencies operate LPRs but without detailed state-mandated restrictions on retention or use. Some police departments have developed their own policies, but there is no statewide requirement for how long data must be kept or what purposes it can be used for. New York does have a civil rights law that provides some general protections against discriminatory surveillance practices, but this is not LPR-specific.

Florida does not have a dedicated LPR law, though various law enforcement agencies throughout the state use the technology. The Florida Department of Law Enforcement operates a statewide database called the Regional Information Sharing Systems (RISS) that may include LPR data from multiple agencies. Without specific legislation, practices vary significantly by agency and jurisdiction.

Many other states—including Indiana, Georgia, Idaho, and others—have minimal or no specific LPR legislation at the state level. In these states, local police departments may use the technology with few restrictions. Some may have internal policies but no public transparency requirements or legal mandates about data retention.

Practical Takeaway: In states with moderate or minimal LPR regulations, oversight depends heavily on individual agency policies rather than statewide law. If you live in such a state, you may want to research what specific policies your local police department has adopted regarding LPR use, retention, and data sharing.

Data Sharing and Inter-Agency Cooperation

One important aspect of LPR regulations involves how data is shared between agencies. An L