We’re Asking the Wisconsin Supreme Court to End Warrantless ALPR Searches
Original reporting by Electronic Frontier Foundation
Automated License Plate Readers (ALPRs) are surveillance devices that capture and store images of license plates, along with their location, date, and time, creating vast databases of individual movements. Today, the Electronic Frontier Foundation (EFF) and the ACLU of Wisconsin filed a petition with the Wisconsin Supreme Court, seeking to establish a constitutional requirement for warrants to conduct retrospective searches of these extensive ALPR databases. The lawsuit, brought on behalf of the Wisconsin Council of Churches and a Green Bay pastor, targets unchecked law enforcement practices in Milwaukee, Racine, Kenosha, and Green Bay.
The Privacy Threat The petitioners argue that ALPRs enable a form of mass surveillance, compiling records of citizens' attendance at medical appointments, religious services, protests, and other sensitive activities. This data, routinely collected, stored, and shared by law enforcement, permits retrospective tracking of individuals and entire communities in ways that were previously impractical or impossible. For religious organizations and their congregants, this unconstrained monitoring poses a unique threat to the privacy inherent in worship, counseling, and community support. The filing asserts that this system upends the principle of individualized suspicion, allowing surveillance vendors to facilitate widespread, warrantless tracking. This action marks EFF's second challenge to warrantless ALPR searches, building on a recent Oklahoma federal court ruling that deemed ALPRs "indiscriminate mass surveillance."
The EFF and ACLU's petition to the Wisconsin Supreme Court marks a critical juncture in the ongoing legal debate over digital privacy. By challenging the warrantless, retrospective searching of vast ALPR databases, the lawsuit seeks to reassert foundational constitutional protections against indiscriminate mass surveillance. Its success would not only safeguard the privacy of Wisconsin residents — particularly those engaged in sensitive activities like religious worship, seeking counsel, or participating in protests — but would also affirm the principle that advanced technology should not erode fundamental rights without proper judicial oversight. This case, following similar challenges and recent favorable rulings, builds on a growing legal consensus that such pervasive, untargeted tracking cannot stand without a warrant.
Protecting Digital Privacy This legal battle extends far beyond the borders of Wisconsin. It represents a vital front in the broader national discourse on how technological advancements intersect with civil liberties, particularly the Fourth Amendment's guarantees against unreasonable searches. A favorable ruling in Wisconsin would send a powerful message nationwide, reinforcing that the ability to collect data en masse does not automatically grant law enforcement the right to search it without individualized suspicion. It would set a significant precedent, potentially influencing courts in other states and shaping future legislative efforts to regulate surveillance technologies. Ultimately, cases like this determine the extent to which individuals can move freely and privately in the digital age, without fear of government tracking every journey to a doctor, a protest, or a place of worship. The court's decision will thus have profound implications for the future of privacy in America.
Frequently asked questions
- What are Automated License Plate Readers (ALPRs) and how do they work for law enforcement?
- Automated License Plate Readers (ALPRs) are camera systems that capture images of license plates, recording their location, date, and time. Law enforcement agencies use them to collect vast amounts of data on vehicle movements. This information is stored in databases, allowing police to retrospectively track the past movements of specific vehicles or even entire communities, which would otherwise be prohibitively difficult or costly.
- Why are privacy advocates challenging law enforcement's use of ALPR data?
- Privacy advocates challenge ALPR data use due to concerns about warrantless mass surveillance. They argue that continuously tracking vehicle movements infringes on constitutional rights, especially when individuals attend sensitive activities like religious services, medical appointments, or protests. Such tracking allows authorities to monitor private associational activities without individualized suspicion, fundamentally altering traditional policing methods and potentially chilling free expression.
- What legal arguments are being made against warrantless searches of ALPR databases?
- Legal challenges against warrantless ALPR database searches argue that they violate constitutional protections against unreasonable searches. Advocates contend that continuously collecting and storing location data, then searching it without a warrant, constitutes a form of mass surveillance that requires probable cause. They assert that state constitutions should mandate a warrant for retrospective ALPR database searches, upholding the principle of individualized suspicion over indiscriminate tracking.