Are Automatic License Plate Readers Unconstitutional?

 Posted on June 13, 2025 in Traffic Violations

The Illinois legislature passed a bill this year that would rewrite the definition of "forcible felony" so that state police can use images from automatic license plate readers (ALPRs) to further apprehension and prosecution of human traffickers. When a license plate number from an ALPR matches one of those in the multi-agency databases, the Illinois State Police are alerted.

Currently, the law allows the use of ALPRs for the investigation of cases that involve vehicular hijacking, terrorism, motor vehicle theft, or any forcible felony (treason, first and second-degree murder, sexual assault, kidnapping, arson, robbery, burglary, and aggravated battery resulting in bodily harm. House Bill 3339 would add human trafficking and involuntary servitude to the list.

While police believe ALPRs are an invaluable tool that allows them to apprehend more people who have committed felony offenses, others question the legality of these cameras and whether they violate the constitutional rights of drivers. If you are charged with a criminal offense and wonder whether the manner in which you were identified is legal or constitutional, speak to a knowledgeable Arlington Heights, IL criminal defense attorney to ensure your rights are protected.

Are Automatic License Plate Readers Legal?

Automatic license plate readers are essentially a surveillance technology that is designed to track the movements of every passing driver. ALPRs are mounted on police cars or on objects like road signs and bridges, using small, high-speed cameras to photograph thousands of license plates per minute.

As of February 2025, state legislators in seven states were taking steps to address these privacy concerns. The scanned license plates are being utilized by approximately 600 local and state police departments, as well as other state and federal agencies, including private businesses such as vehicle insurance companies and vehicle repossession companies.

Currently, only 16 states have any real restrictions on the use of ALPRs. Eight of those states limit how long the data can be kept, six states restrict how the data is used by government and law enforcement, and four states exempt the data under public records laws.

What Are the Laws in Illinois Regarding ALPRs?

A lawsuit was filed last year in Illinois that would have ended the use of ALPRs on the basis that they are an unconstitutional form of surveillance against every driver in the state.  A U.S. District Judge agreed with the state of Illinois in a March 31, 2025, ruling.

The judge stated that photograph captures and the collection of data from ALPRs do not rise to the level of searches, which are limited under the Fourth Amendment. The judge went on to say that a person traveling on public roadways has no reasonable expectation of privacy and that Illinois’s use of ALPRs is not intrusive enough to violate the constitutional rights of drivers.

Illinois first authorized ALPRs in 2019 under the Tamera Clayton Expressway Camera Act. Initially, about 300 plate readers were installed along Cook County’s major expressway interstate highways in and out of Chicago, but that use has spread over the past six years to other communities in Illinois.   

When ALPR Technology Goes Wrong

ALPR technology can create serious problems that are not being addressed. Misidentified drivers have been stopped at gunpoint, a Massachusetts police officer misused ALPR to stalk ex-lovers, and a New Jersey Officer used the technology to intimidate a man for befriending the ex-girlfriend of a fellow officer.

A California man lost the use of his right arm after a police K-9 attacked him as a result of an erroneous report of a stolen rental car based on ALPR. Oakland police gave the FBI unrestricted access to ALPRs – a violation of the city’s policy. There are many more such instances, plus the privacy risk of ALPRs is real.

Contact a Rolling Meadows, IL Criminal Defense Lawyer

If you are facing criminal charges, it is important that you have an experienced Arlington Heights, IL criminal defense attorney from Scott F. Anderson, Attorney at Law building a comprehensive defense on your behalf. Attorney Anderson has over 25 years of experience in criminal law defense, both as a prosecutor and now as a criminal defense attorney. Call 847-253-3400 to schedule your free consultation.