Independent studies show minimal crime reduction. Documented abuses, data breaches, and Supreme Court precedent suggest mass license plate tracking without warrants is a constitutional problem, and there is a proven alternative.
Do These Cameras Actually Work?
TL;DR: Multiple independent studies found little to no crime reduction from ALPR deployment. Flock's own effectiveness claims come from company-administered surveys with no independent verification.
Before accepting mass surveillance, we should ask: Does it actually reduce crime?
Multiple independent studies found little to no crime reduction from ALPR deployment:
Mesa, Arizona (2012): No significant impact on crime
Alexandria & Fairfax County, VA (2011): No significant crime reduction
Baton Rouge, Louisiana (2019): No significant crime reduction
Atlantic City (2025): No reduction in violent crime overall
Comprehensive Review (Koper et al., 2019):
"Little evidence that ALPRs reduce crime" and "less evidence on impact on clearance/solve rates"
Flock's Self-Conducted Survey
Flock has marketed a claim that its technology is involved in solving around 10% of reported crime in the United States. We paraphrase rather than quote because the company has stated it in varying forms across its marketing materials. Whatever the exact phrasing, the underlying study has the same problems:
Study conducted by Flock employees with academic researchers' names added for credibility
Researcher Raises Concerns: Johnny Nhan of Texas Christian University, who oversaw the academic review of Flock's effectiveness study, now has serious doubts about the methodology. According to 404 Media, Nhan said he "would have done things much differently" and discovered that "the information that is collected by the police departments are too varied and incomplete for us to do any type of meaningful statistical analysis on them." This led him to pivot away from future Flock research entirely.
The Trade-Off: Comprehensive tracking of millions of innocent people, data breach risks, chilling effects on First Amendment activities, and disproportionate impact on vulnerable communities, all for minimal demonstrated crime reduction benefits.
What Can Go Wrong: Documented Abuses
TL;DR: ALPR systems have been abused for stalking and exposed to data breaches. Even with policies prohibiting misuse, enforcement relies on police self-auditing.
Even well-intentioned surveillance systems can be abused. Here's what has actually happened in other communities:
Individual Officer Abuse
A Kansas police chief used Flock roughly 228 times over four months to track a woman he had been in a relationship with, as reported by 404 Media. We are still working to confirm the department name and the case disposition from primary records; if you have them, send them to us
Officers in other jurisdictions using law enforcement databases to stalk ex-partners and pursue personal grievances
No apparent disciplinary action in many documented cases
Cybersecurity Vulnerabilities
June 2024 CISA bulletin: 7 vulnerabilities in Motorola/Vigilant ALPRs
Credentials for a number of Flock customer accounts have been reported stolen and circulated on criminal marketplaces. We have not yet been able to pin this to a primary source and have removed the specific "35+ accounts" figure pending confirmation.
Border vendor Perceptics hacked with data published online (2019)
In fairness to Grafton: Flock did not require multi-factor authentication on legacy accounts, and only enabled it by default for customers onboarded from November 2024. Grafton's transparency portal states the department requires MFA. Flock's own portal also asserts that its cloud environment "has never been breached" and lists SOC 2 Type II, ISO 27001 and FedRAMP compliance. Those are vendor claims rather than independent findings, but they are the department's stated position and residents should weigh them.
FTC Investigation Requested: Senator Ron Wyden and Rep. Krishnamoorthi called for investigation in 2025, alleging Flock "failing to implement cybersecurity protections and needlessly exposing Americans' sensitive personal data to theft by hackers and foreign spies."
The Data Breach Reality
Law enforcement agencies and their vendors experience frequent data breaches, putting ALPR location data at risk:
Law enforcement vendors: Thomson Reuters (2024), Perceptics (2019), and numerous police departments have experienced breaches exposing sensitive investigative data
No uniform standards: Most local law enforcement agencies lack dedicated cybersecurity staff or mandatory security requirements
Multi-agency access amplifies risk: With 1,294 organizations accessing Grafton's data, a breach at any one agency could expose your location history
Key Risk: When Grafton's ALPR data is accessed and downloaded by agencies across 32 states, that data is only as secure as the least secure agency in the network. A breach at a small-town police department in another state could expose the complete movement history of Grafton residents: where you drive, when you visit sensitive locations (medical facilities, places of worship, political events), and your daily patterns.
Questions Grafton hasn't answered:
What cybersecurity standards are required of the 1,294 organizations that can access our data?
Who monitors whether agencies properly secure downloaded ALPR data?
What happens to Grafton residents' data when it's breached at another agency?
Does the Village have liability insurance for data breaches affecting residents?
Why This May Violate the Fourth Amendment
TL;DR: In Carpenter v. United States (2018) the Supreme Court held that acquiring 127 days of historical cell phone location data was a Fourth Amendment search. Carpenter was expressly narrow, and courts have so far mostly declined to extend it to license plate readers. We think that is wrong, and we set out below both why and where the argument is currently losing.
The Core Constitutional Concern
Automated License Plate Readers create comprehensive, searchable records of everyone's movements (innocent people and criminals alike) without warrants, probable cause, or individualized suspicion. This resembles the general warrants and writs of assistance that the Fourth Amendment was designed to prohibit.
The Fourth Amendment:
"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause..."
The Carpenter Precedent (2018)
In Carpenter v. United States, the Supreme Court held that accessing 127 days of historical cell-site location data was a Fourth Amendment search requiring a warrant. Key findings:
Data was "detailed, encyclopedic, and effortlessly compiled"
Covered an extended period (127 days)
Generated automatically without user action
Technology was "indispensable to participation in modern society"
Enabled retrospective "time travel" tracking
Carpenter Was Deliberately Narrow, and That Matters
It is often said that Carpenter "ruled that comprehensive location tracking requires warrants." That overstates it, and anyone who reads the opinion will notice. The Court went out of its way to limit the decision:
"Our decision today is a narrow one. We do not express a view on matters not before us... Nor do we call into question conventional surveillance techniques and tools, such as security cameras."
That sentence is precisely what courts have relied on to uphold ALPR systems, in Norfolk and in the Fifth Circuit alike. Any honest argument about Grafton's cameras has to answer it rather than pretend it isn't there.
The answer is that a Flock network is not a security camera. A security camera records what passes in front of it and leaves the footage unread until someone has a reason to go look. Grafton's system converts every passing vehicle into a structured database record, indexed by plate and by vehicle characteristics, retained for 30 days, and made queryable by 1,294 organizations who never have to ask Grafton's permission or tell anyone they looked. The question Carpenter's "security cameras" caveat leaves open is whether a searchable national index of everyone's movements is the same kind of thing as a camera on a wall. We think the answer is obviously no. So far, the courts have mostly disagreed.
How Grafton's ALPRs Match Carpenter's Concerns
✓ Detailed, encyclopedic, effortlessly compiled
✓ Covers extended periods (30-day retention)
✓ Automatic, no driver action required
✓ Driving is indispensable in car-dependent communities
✓ Enables retrospective searches ("where was this car 2 weeks ago?")
✓ Tracks innocent people without suspicion
Where the Law Actually Stands
TL;DR: Courts have so far mostly sided with police on ALPRs, including a federal appellate ruling in 2026 and a loss for the plaintiffs in the leading Flock case. The Supreme Court's June 2026 decision in Chatrie extended Carpenter to other digital location data but did not mention ALPRs. No Wisconsin court has addressed the question, which means this is a decision for the Village Board, not the courts.
We would rather tell you where we are losing than have you find out from someone else. Here is the current state of play.
1. The Losses
United States v. Porter, No. 25-60163 (5th Cir. Mar. 17, 2026). A federal appellate court has now ruled. The Fifth Circuit held that using an ALPR network to generate periodic location hits on public roads is not a Fourth Amendment search. The court distinguished Carpenter on the grounds that the network at issue was limited, roughly ten cameras in one Mississippi town, and produced only intermittent hits rather than the continuous, comprehensive picture of a life that troubled the Court in Carpenter. Earlier versions of this page said no federal appellate court had ruled post-Carpenter. That is no longer true.
Schmidt v. City of Norfolk, No. 2:24-cv-621 (E.D. Va.). This is the leading challenge to a Flock system specifically, brought by the Institute for Justice. The plaintiffs lost. On January 27, 2026, the district court granted summary judgment to the City, holding that Norfolk's roughly 200-camera network did not track "the whole of a person's movements" and so did not invade a reasonable expectation of privacy. The case is on appeal to the Fourth Circuit as No. 26-1227, fully briefed. The ACLU, ACLU of Virginia and EFF filed a joint amicus brief on April 20, 2026; the Cato Institute and the New Civil Liberties Alliance filed separately. No ruling yet.
Other courts have split on narrower facts. A Massachusetts court found four cameras at two locations insufficient to trigger the Fourth Amendment. Virginia state courts reached mixed results on Norfolk's system before the federal case.
2. Why the Reasoning Is Contested, and Where Grafton Sits
Both Porter and Schmidt turn on the same idea: that these networks are too sparse to reconstruct "the whole of a person's movements." That reasoning has a scaling problem, and Grafton illustrates it.
Norfolk lost with better privacy protections than Grafton has. Virginia caps ALPR retention at 21 days by statute (HB 2724, effective July 1, 2025) and bars Virginia agencies from sharing ALPR data with out-of-state law enforcement absent a warrant, subpoena, or court order. Grafton retains 30 days under no statutory cap at all, and shares with 1,294 organizations across 32 states with no such restriction. The system a federal court upheld is meaningfully more restrained than Grafton's.
The "sparse network" argument gets weaker as the network grows. Porter involved about ten cameras in one town. But Grafton's cameras are not an isolated ten. They are nodes in a network that, per DeFlock's mapping, exceeds 95,000 Flock cameras nationally. An officer querying from another state is not searching nine cameras; they are searching everything Grafton can reach.
Aggregation is the whole point of the product. The constitutional theory that ALPRs capture only "discrete observations on public roads" describes a single camera. It does not describe a searchable index built specifically so that discrete observations can be assembled into a travel history.
3. What Chatrie Changes, and What It Doesn't
Chatrie v. United States, No. 25-112 (U.S. June 29, 2026). The Supreme Court held 6-3, in an opinion by Justice Kagan, that police acquisition of a person's Google Location History through a geofence warrant is a Fourth Amendment search. It is the Court's first major digital privacy decision in eight years and it extends Carpenter's logic to third-party-held location data, including over short time windows.
The honest caveat: Chatrie does not mention ALPRs. Flock Safety has already published a rebuttal arguing the decision does not apply, on the grounds that license plate reads are "discrete observations of vehicles on public roadways" rather than continuous personal location tracking. That argument will be made to the Fourth Circuit in the Norfolk appeal, and it may win.
But Chatrie matters for two reasons. It confirms the Court is willing to extend Carpenter rather than confine it to cell-site data, and it undercuts the assumption that short collection windows are constitutionally safe. Grafton's 30-day window is not obviously on the right side of that line.
4. No Wisconsin Court Has Addressed This
This is the practical point. Wisconsin has no ALPR statute and no Wisconsin court ruling on ALPR constitutionality. Nobody is coming to resolve this for Grafton.
That cuts both ways, and we will say so plainly: the current weight of authority suggests Grafton's system is probably lawful today. "Probably lawful" is not the same as "good policy." Courts set a floor, not a standard. The Village Board can choose shorter retention, warrant requirements for historical searches, and real audit transparency regardless of what the Fifth Circuit thinks, and it does not need to wait for a court to tell it to.
The Greater Good Argument Doesn't Justify Unconstitutional Searches
Police could solve more crimes if they could search every home without warrants, read everyone's emails without subpoenas, track everyone's phones without court orders, or install cameras in every private space. We don't allow these things because we value constitutional rights over efficiency. The same principle applies to mass ALPR surveillance. Catching criminals doesn't justify treating every citizen as a suspect under constant surveillance.
The "Buying Data" Loophole
Even if courts require warrants for ALPR searches, government can potentially bypass this protection by purchasing data from private companies instead of compelling its production.
The Third-Party Doctrine Problem
Traditional doctrine: no privacy in information "voluntarily" given to third parties
Carpenter limited this for comprehensive digital surveillance
But if government BUYS data on the open market, some argue this isn't "state action"
Creates loophole: warrant required for compelled production, but not for purchased data?
This Already Happens
NSA and FBI purchase location data from commercial data brokers (per Sen. Ron Wyden)
Private ALPR vendors maintain commercial databases with 6.5+ billion scans for sale
Vigilant Solutions sells ALPR data to private entities and government
No warrant, no subpoena, just payment
Why This Matters for Grafton
Flock Safety owns Grafton's camera data
Template contract grants Flock "worldwide, perpetual, royalty-free license" to share
Even if courts require warrants, federal agencies could potentially buy access
Local policies may be superseded by Flock's contract terms
Wisconsin's Regulatory Vacuum
TL;DR: Wisconsin has NO state laws regulating ALPRs. 221 Wisconsin agencies used Flock between January and May 2025, with no state-level review, uniform standards, or accountability.
Wisconsin has enacted NO statutes regulating ALPRs:
No data retention limits
No warrant requirements
No transparency mandates
No oversight mechanisms
No community approval processes
No state agency monitoring deployment
A Wisconsin Examiner analysis of Flock audit data found 221 Wisconsin agencies used the system between January and May 2025, all with no state-level review, uniform standards, or accountability.
Existing Laws Don't Apply
Privacy statutes only protect "private places" - not public roads
Electronic surveillance laws focus on wiretapping, not visual surveillance
Proposed Wisconsin Data Privacy Act explicitly exempts government entities
ACLU-Wisconsin Advocacy
Calling for Community Control Over Police Surveillance (CCOPS) ordinances requiring:
Transparent decision-making
Public input before deployment
Regular independent audits
City council approval
Madison remains the only Wisconsin municipality to adopt a CCOPS ordinance, per ACLU of Wisconsin's CCOPS campaign; roughly 26 jurisdictions nationwide have adopted comparable ordinances. Milwaukee, Grafton, and every other Wisconsin municipality operate without these safeguards, even where individual Flock contracts have been rejected by other means.
What Civil Liberties Organizations Say
ACLU, "Get the Flock Out" campaign (2026):
The ACLU estimates Flock now operates between 80,000 and 100,000 devices across more than 5,000 U.S. communities, performing more than 20 billion license plate scans every month, and describes it as a form of mass surveillance unlike any seen before in American life.
Key ACLU Concerns
Mission Creep: Expanding from plates to vehicle fingerprints, bumper stickers (First Amendment concerns)
Disproportionate Impact: Enables over-policing in communities of color
Lack of Accountability: No legal requirement to honor 30-day retention; company can change policies anytime
Hot List Accuracy: The NCIC database that feeds ALPR alerts has long-documented accuracy problems, and a wrong hit means an armed stop of an innocent driver
Electronic Frontier Foundation Findings
99.9% of scans are unrelated to any criminal investigation or public safety interest at the time of collection (EFF, Data Driven 2: California Dragnet, April 2021, analyzing over a billion California ALPR scans). A 2018 EFF and MuckRock review of 200 agencies nationwide found 99.5% of plates scanned were not on any hot list.
Roughly 1 in 10 plates has its issuing state misread (EFF, "The Human Toll of ALPR Errors," November 2024). This is a state-field error, not an overall misidentification rate, but it matters: a state mismatch can cause a scanner to flag an innocent driver's car as a wanted vehicle from somewhere else, and EFF documents real stops that resulted.
Disproportionate deployment in low-income communities and communities of color
Data breaches affecting millions of innocent people's location history
A note on our own numbers. Earlier versions of this page used "99.95%" and attributed a "10% misidentification error rate" to the ACLU. The first was a narrower sub-finding presented as a headline figure; the second is an EFF finding about state-field misreads specifically, not an ACLU figure and not an overall error rate. Both have been corrected. Note also that "not on a hot list" and "not related to an active investigation" are not the same as "innocent," and we have stopped using them interchangeably.
Recommended Safeguards
If ALPRs deployed despite opposition:
3-minute deletion for non-hits (New Hampshire model)
Warrant requirements for historical searches
Hot list certification and accuracy audits
No third-party sharing
Community Control Over Police Surveillance (CCOPS) ordinances requiring council approval
Regular independent audits with public reporting
Restricted access to trained personnel only
Communities Are Removing and Rejecting Flock Cameras
TL;DR: More than 30 communities across the political spectrum have removed, suspended or rejected Flock cameras after discovering unauthorized federal access, constitutional concerns, and minimal crime reduction benefits. Trackers counting cumulative contract terminations since 2021 put the total well above 80. Wisconsin is among the states with the most cancellations.
Grafton isn't alone in deploying these cameras, but a growing number of communities are reversing course. Because this count keeps moving, treat the figures here as a floor and check a live tracker such as whoapprovedthis.org for the current number.
Municipal Removals & Terminations
Evanston, IL: Forced to remove 19 cameras after state audit found unauthorized federal access violated Illinois law
Eugene, OR: Terminated its contract effective immediately on December 5, 2025. When Flock said it would not begin removing cameras until January 26, city staff took them down themselves, pulling 55 of 57 by December 19. Springfield and Lane County ended their Flock relationships in the same period
Denver, CO: All 110 cameras removed at contract expiry on March 31, 2026, and replaced with 50 Axon cameras under stricter controls on a $150,000 one-year contract (approved 7-6)
Stanwood & Sedro-Woolley, WA: Shut down after judge ruled footage is public record
Council Rejections
Denver, CO: City Council unanimously rejected a two-year, $666,000 extension in May 2025. The mayor's office then signed a $498,500 extension instead, $1,500 below the $500,000 threshold that would have required council approval. Council members publicly accused the administration of structuring the deal to evade oversight. See the removal outcome above
Cambridge, MA: Unanimously voted to pause 16 cameras
Austin, TX: Terminated contract after community pushback
Oak Park, IL: Terminated over federal access and state law violations
Wisconsin is not an outlier here. Reporting on the 2026 cancellation wave puts Wisconsin among the states with the most Flock rejections, cancellations and deactivations of any state in the country. Grafton's neighbours are already having this debate.
Bipartisan Opposition
Sedona, AZ: Conservative-led grassroots campaign led unanimous council vote to remove cameras
Tennessee: Right-wing activists opposing "tracking system for law-abiding citizens"
Opposition spans political spectrum: conservatives cite government overreach; progressives cite privacy concerns
This isn't a partisan issue. Communities on both the left and right are recognizing that comprehensive surveillance of innocent people is incompatible with a free society.
The Better Alternative: Flag-and-Discard
TL;DR: New Hampshire's model shows you can find stolen cars and wanted suspects while deleting data on innocent people within 3 minutes. You can have effective law enforcement AND constitutional protections.
ALPRs can serve legitimate law enforcement purposes WITHOUT creating a surveillance database of innocent people.
Still enables real-time alerts for actual criminal investigations
Eliminates dragnet surveillance of innocent people
Why This Works
✓ Finds stolen cars and missing persons
✓ Alerts for wanted suspects
✓ No comprehensive tracking database
✓ No Fourth Amendment concerns
✓ No data breach risk for innocent people
✓ No mission creep to tracking bumper stickers or political affiliations
ACLU Position: New Hampshire's 3-minute deletion for non-hits is the "gold standard" - it serves legitimate law enforcement needs while protecting civil liberties.
Two honest caveats, because opponents will raise both:
No court has blessed the New Hampshire model either. Saying it has "no constitutional concerns" would be an assertion, not a fact. What can be said is that a system holding no retrospective database of non-hits has dramatically less exposure to the aggregation argument that Carpenter and Chatrie turn on, because there is nothing to aggregate.
New Hampshire does retain hits. The 3-minute purge applies to plates that do not match a hot list. Vehicles that do match are retained for investigation, as they should be. "No database" is a simplification we have corrected in the table above.
And the framework is permanent. New Hampshire's ALPR statute, RSA 261:75-b, originally carried a scheduled repeal effective January 1, 2027. HB 1059 removed that sunset; Governor Ayotte signed it on May 28, 2026 as Chapter 88. Anyone who tells you this site is citing a statute that is about to expire is working from stale information.
Grafton vs. New Hampshire: A Comparison
Feature
Grafton's System
New Hampshire Model
Data Retention
30 days
3 minutes
Warrant Required
No
N/A for non-hits (purged in 3 minutes); hits are retained
Tracks Innocent People
Yes. About 99.6% of vehicles Grafton detected in the 30 days to Aug 7, 2026 produced no hotlist hit
No retrospective record of non-hits
External Agency Access
1,294 organizations
No sharing
Finds Stolen Cars
Yes
Yes
Constitutional Exposure
Contested and untested in Wisconsin
Substantially reduced
Why Grafton's 30-Day Retention Is Problematic
Creates searchable database of every vehicle that entered Grafton over past month
Enables retrospective investigations without warrants
Allows searches based on vehicle characteristics (bumper stickers, roof racks)
Accessible to 1,294 organizations for unrelated investigations
No individual suspicion or probable cause required
What Now?
Grafton can keep the investigative benefits and drop the mass surveillance. Here is how.