Automated License Plate Recognition (ALPR) FAQ
Message From the Sheriff
Turn on the news, open a tab on the internet, or log into social media, and it doesn’t take long to see a story or post about license plate readers. A national conversation about automated license plate recognition (ALPR) technology, (specifically Flock, which is one of many ALPR brands) has spiked in interest.
I would like to take the opportunity to talk to our citizens about ALPR technology. We have put together educational materials to provide clarity as to how the Johnson County Sheriff’s Office uses it and the care that goes into keeping the data secure.
It is my hope that our residents can see how these tools are important for law enforcement’s ability to keep citizens safe. This technology has helped our deputies in Johnson County locate missing people, recover stolen vehicles, and apprehend an armed man wanted after threatening a daycare.
Strong safeguards and effective law enforcement are not mutually exclusive. Public safety and data privacy are both our responsibility.
-Sheriff Byron Roberson
Our community deserves clear and accurate information about how automated license plate recognition (ALPR) technology works, its limitations, and its role in helping law enforcement protect communities and save lives. The Johnson County Sheriff’s Office is committed to using ALPR technology responsibly.
JCSO has used license plate recognition systems since 2022, and law enforcement agencies throughout the United States have used them for more than 20 years. As a proven public safety tool, they provide critical leads when information is limited and time matters.
As the technology evolves, we work with local, regional and national partners and professional associations to strengthen the principles that guide its responsible and effective use in law enforcement. The information on this page reflects both our agency’s established practices and the broader principles developed through this collaboration.
ALPR is a valuable investigative tool, and JCSO recognizes that responsible use requires clear limits, human verification, restricted access, auditing, appropriate retention and accountability.
ALPR devices capture a still photograph of the rear of a vehicle as it passes through a publicly accessible roadway. The record contains the plate, vehicle image, date and time, and camera location. Kansas law requires license plates to be clearly visible and legible. Plate information may be compared with lists associated with legitimate public safety concerns.
ALPR does not identify the driver or occupants. It does not provide continuous video or GPS tracking.
License plate readers are important to law enforcement because they help officers identify and locate vehicles connected to criminal activity more quickly and accurately. LPR-generated information can:
- Help locate stolen vehicles and vehicles associated with wanted individuals.
- Improve response times during emergencies, including AMBER and Silver Alerts.
- Provide time-stamped information that supports criminal and death investigations.
- Help agencies focus personnel and resources by automating routine license plate checks.
- Improve coordination between jurisdictions when vehicles travel outside an agency’s boundaries.
Examples of JCSO ALPR use:
- July 2024: After an intelligence bulletin was distributed via Metro List, we identified a vehicle connected to a homicide in Kansas City, Missouri, was frequently present in Johnson County. An ALPR email alert was created for the vehicle. Within days, an alert was received by a deputy who was in the area on I‑35. The vehicle was located and stopped with assistance from the Kansas Highway Patrol. The driver was detained and later confessed to the homicide.
- April 2025: While attempting to locate a subject wanted for threatening to shoot up a daycare, LPR data showed his vehicle traveling to Iowa. The next day, the vehicle began returning south toward the Kansas City area. Deputies positioned units near his apartment, and when he arrived, he fled on foot but was apprehended. The subject was armed with a handgun.
- June 2025: During an investigation involving a suspect wanted for the rape of a child, LPR hits identified a vehicle registered to the suspect traveling through a specific area. Although no residence could be located nearby, units positioned at intersections observed the vehicle shortly afterward. The suspect was positively identified, followed into Olathe, and arrested.
- May 2026: While searching for a suspect wanted for aggravated assault and robbery, the suspect was observed at a location of interest in Kansas City, Missouri, but left before surveillance could continue due to heavy criminal activity in the area. Using the vehicle description, along with supporting investigative information, we identified the vehicle through LPR searches. The suspect was later found driving that vehicle, arrested, and a handgun, illegally possessed, was recovered.
- July 2026: An ATM technician was robbed in which approximately $150,000 was taken. After obtaining a license plate from traffic camera footage for one of the suspect vehicles, an alert was entered into the LPR system. Within hours, the vehicle was detected traveling southbound out of the metro area. Coordination with the Missouri Highway Patrol, along with successive LPR hits, led to the vehicle’s location. A suspect was arrested, and nearly $60,000 of the stolen cash was recovered.
JCSO has also used ALPR information to safely locate missing people and help establish timelines in death investigations.
Access to ALPR information is limited to authorized personnel. Every search must include a case number and is tied to the employee who conducted it. Search activity is recorded and can be audited. Unauthorized use violates JCSO policy and may result in disciplinary action or criminal investigation.
ALPR records are retained for a maximum of 90 days and then deleted unless they are preserved as part of an investigation.
JCSO may share ALPR information with authorized law enforcement agencies for legitimate investigative or public safety purposes. This allows agencies to follow leads across jurisdictional lines, locate missing or kidnapped people, connect related crimes and apprehend dangerous offenders. ALPR information is not sold or used for commercial purposes.
Can law enforcement search for any vehicle at any time for any reason?
No. Before an ALPR search can be conducted, a crime, missing-person case or other public safety matter must already be documented. Every search requires a case number and must involve a vehicle relevant to that case. The system records the employee who conducted the search and the associated case number which is documented and reviewed when an audit is conducted.
Does JCSO use ALPR to monitor everyday travel and look for possible wrongdoing?
No. ALPR searches must relate to a documented criminal investigation, missing-person case, or other public safety matter. The information may be used to determine when and where a vehicle connected to that case was observed.
Does JCSO use ALPR to enforce speeding and red-light violations?
No. JCSO uses ALPR as an investigative tool, not for automated traffic enforcement. The cameras do not measure speed or determine whether a vehicle ran a red light.
Does ALPR continuously track vehicles like GPS?
No. ALPR records a vehicle only when it passes a camera. It does not provide continuous location information or show everywhere a vehicle has traveled.
Does an ALPR alert automatically result in a stop or arrest?
No. An ALPR alert is an investigative lead and does not determine guilt or identify of who is driving. Investigators must evaluate and corroborate, just like other investigative leads, before taking enforcement action.
License plates are publicly displayed, and ALPR records when and where a vehicle was observed in a public location. Courts, including federal appellate courts, have generally held that the limited use of ALPR information for an investigation does not violate the Fourth Amendment.
JCSO recognizes that collecting and retaining vehicle observations raises reasonable privacy questions. Access is limited to documented law enforcement and public safety purposes, and the technology is used in accordance with agency policy and applicable law.
The Major County Sheriffs of America offers a more detailed explanation of how the Fourth Amendment applies to ALPR technology.