There is no comprehensive federal law specifically regulating ALPR technology. The primary legal question is whether mass collection and searching of ALPR data constitutes a "search" under the Fourth Amendment, which protects against unreasonable searches and seizures. The Supreme Court's 2018 decision in Carpenter v. United States established that the government needs a warrant to access historical cell-site location information — a precedent that privacy advocates argue should extend to ALPR data, which is similarly location-tracking. The EFF has argued that ALPR databases create the same kind of "comprehensive tracking" that the Carpenter decision was designed to prevent. However, no federal court has yet ruled definitively on whether ALPR searches require a warrant.
States vary widely in how they regulate ALPR technology. California, for example, requires law enforcement to have a data-retention policy and limits retention of non-hit data, though the state has not banned ALPR outright. New Hampshire banned the use of ALPR data for anything other than the purpose for which it was collected. Maine has restricted the use of ALPR technology by state agencies. Arkansas passed a law requiring a warrant for ALPR data searches. Virginia limits data retention to 30 days for non-hit scans. Many states, however, have no ALPR-specific laws at all, leaving deployment decisions to local police departments and city councils. The ACLU maintains a tracker of state-level ALPR legislation.
Multiple lawsuits are challenging Flock Safety's practices. In 2025, the ACLU filed suits arguing that Flock's nationwide searchable database constitutes warrantless mass surveillance. The EFF has supported litigation challenging the use of ALPR data without a warrant, citing the Carpenter precedent. In one notable case, a Texas sheriff used Flock's nationwide search function to locate a woman who had a self-administered abortion — the EFF documented this case and it has become a flashpoint in the debate over ALPR oversight. In August 2025, members of Congress launched a formal investigation into Flock's surveillance practices, demanding records about data sharing with federal immigration agencies.
In most jurisdictions, yes. Because ALPR data is collected in public — where there is no reasonable expectation of privacy — courts have generally held that police do not need a warrant to collect or search it. However, the Carpenter decision has opened the door to challenges of this reasoning. The EFF has argued that while a single ALPR scan may not constitute a search, aggregated data that reveals patterns of life over time crosses the threshold into Fourth Amendment territory. A few states, including Arkansas, now require a warrant for ALPR database searches. Privacy advocates are pushing for similar requirements nationwide.
Yes. Cities have broad authority to decide whether to contract with Flock Safety or other ALPR vendors. A growing list of municipalities have done exactly that — deactivating cameras, canceling contracts, or passing ordinances prohibiting ALPR deployment. The ACLU's "Get the Flock Out" campaign provides advocacy toolkits for residents who want to push their local governments to reject ALPR surveillance. At least 30 localities have deactivated or canceled Flock contracts since the beginning of 2025, including Flagstaff, AZ; Cambridge, MA; Eugene, OR; and Santa Cruz, CA.
Flock Safety sells cameras not only to police but also to HOAs, businesses, and neighborhood watch groups. Private use of ALPR is even less regulated than law enforcement use. In many states, there are no restrictions on private entities collecting and retaining plate data. Flock's cloud model means that data from private cameras is pooled with law enforcement data, effectively deputizing private surveillance for police purposes. The ACLU has flagged this as a particular concern, as it blurs the line between community security and mass surveillance.
Is it legal for police to use Flock cameras without a warrant?
In most states, yes. Courts have generally held that license plates are visible in public and therefore not subject to Fourth Amendment protection. However, the 2018 Carpenter decision and state laws like Arkansas's warrant requirement are challenging this. Several lawsuits are currently testing whether aggregated ALPR data requires a warrant.
Which states have banned Flock cameras?
No state has enacted a blanket ban on Flock cameras, but several states — including Arkansas, Maine, New Hampshire, and Virginia — have passed laws restricting ALPR data collection, retention, or sharing. Over 30 cities have individually deactivated or canceled Flock contracts.
Can I sue over ALPR surveillance?
It is difficult but not impossible. Several lawsuits backed by the ACLU and EFF are currently challenging ALPR practices on Fourth Amendment grounds. Standing — the legal right to sue — is a hurdle, as plaintiffs must show concrete harm. Consult a civil rights attorney if you believe you have been affected.
Is Flock Safety regulated by the federal government?
There is no federal agency specifically tasked with regulating ALPR technology. In August 2025, members of Congress launched a formal investigation into Flock's practices, but no federal ALPR law has been passed. Regulation is currently left to states and municipalities.
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