In a key legal challenge, the Electronic Frontier Foundation and ACLU have filed an amicus brief urging the Sixth Circuit Court of Appeals to require police to obtain warrants before conducting searches using automated license plate reader (ALPR) data, highlighting the extensive surveillance capabilities these systems enable.
- EFF and ACLU challenge warrantless ALPR surveillance in Sixth Circuit
- ALPR systems create detailed historical movement records
- Case could reshape Fourth Amendment protections for location data
What happened
The Electronic Frontier Foundation and the American Civil Liberties Union filed an amicus brief in the ongoing Sixth Circuit appeal of United States v. Sturdivant. The case involves police officers who used automated license plate reader (ALPR) databases to identify and track a suspect’s vehicle movements without obtaining a warrant. Police identified the suspect’s vehicle by make, model, and color via surveillance footage and then ran open-ended searches of ALPR data from companies like Flock and ELSAG, which showed the defendant’s car near robbery sites and led to his arrest.
The defendant moved to suppress the ALPR evidence, arguing it violated his Fourth Amendment rights. However, the district court rejected this, ruling that because license plates are visible to the public, tracking them did not invade a reasonable expectation of privacy. EFF and ACLU’s brief counters this ruling, explaining that ALPR systems function very differently from casual public observation, constituting a pervasive surveillance capability that records detailed location histories and amounts to a search under the Constitution.
Why it matters
This case explores the constitutional limits of law enforcement’s use of mass surveillance technology. ALPRs automatically capture millions of license plate images daily, compiling extensive location data about countless individuals, not just suspects. Unlike one-time visual observations, ALPRs create searchable databases enabling retrospective reviews of suspects’ past movements. This raises significant privacy concerns, as individuals’ whereabouts can be tracked broadly and indefinitely without their knowledge or judicial oversight.
Previous court decisions have expressed skepticism of warrantless mass location tracking, with some recent federal rulings acknowledging ALPRs as a form of indiscriminate surveillance. A ruling requiring warrants for ALPR searches would establish important protections under the Fourth Amendment, signaling limits on government overreach in the use of advancing surveillance technologies and ensuring judicial review before these data are accessed.
What to watch next
The Sixth Circuit Court’s decision in United States v. Sturdivant will be closely watched by privacy advocates, law enforcement entities, and technology policy experts. A ruling overturning the district court could reshape how courts treat digital location data under the Fourth Amendment and compel police to obtain warrants for accessing ALPR data nationwide.
In parallel, ongoing challenges to ALPR use in other jurisdictions, such as lawsuits and local policy reforms, reflect growing public and legal scrutiny of mass surveillance tools. Developments here may influence broader discussions around privacy, data retention, and oversight of law enforcement surveillance innovations.