AI Weapons Detection Screening

These systems screen people walking through a portal, using sensors and pattern recognition intended to identify the signature of a weapon while ignoring everyday items. They are marketed as a faster, less intrusive alternative to metal detectors: no emptying pockets, no queue, high throughput.

The dominant supplier is Evolv Technologies, whose Express scanners are used in over 800 schools across 40 states, alongside stadiums, hospitals and transport systems. School systems make up around half its business. The company has been backed by prominent investors including Bill Gates.

WHAT THE COMPANY CLAIMED

Evolv marketed the scanners as able to distinguish weapons from everyday objects using AI, claiming they could identify the unique signatures of tens of thousands of weapons and separate guns, bombs and large tactical knives from keys and laptops. It advertised screening of up to 1,000 students in fifteen minutes, ten times faster than traditional metal detectors, and positioned the technology as more accurate, efficient and cost-effective than metal detection.

THE FTC ACTION

In November 2024 the Federal Trade Commission filed a complaint and proposed settlement alleging Evolv deceptively advertised that its scanners would detect all weapons, ignore harmless personal items, and outperform metal detectors through the use of artificial intelligence.

The specific findings are the substance of this page.

The scanners failed in several instances to detect weapons in schools while flagging harmless items students routinely carry — laptops, binders, water bottles. In October 2022 an Express scanner failed to detect a seven-inch knife brought into a school, which was then used to stab a student. After that incident the school raised the sensitivity setting, which produced a 50% false alarm rate.

A 2021 test at a Major League Soccer stadium in Columbus, Ohio found the scanners missed two small handguns and detected knives only 58% of the time. In one deployment across twenty subway stations over a month, the scanners produced 118 false positives, recovered 12 knives, and detected no firearms at all. In some school settings the scanners flagged more than 85,000 false positives on laptops between August 2023 and April 2024.

The FTC also alleged that Evolv altered a report from the National Center for Spectator Sports Safety and Security to remove negative findings about its scanners.

The commission further noted that Evolv's own remedies — a higher sensitivity setting, plus conveyor belts and manual diversion of harmless items — made the system function more like the lower-cost metal detectors it was sold as superior to, while requiring additional staffing.

THE SETTLEMENT

Evolv was barred from making unsupported claims about its products' ability to detect weapons using artificial intelligence, and required to notify certain K-12 customers with contracts signed between April 2022 and June 2023 that they could cancel. Customers who had run a 30-day trial or bought fifteen or more scanners were excluded from that option.

The company's own position is recorded: it stated it disagrees with the FTC's allegations, has not admitted wrongdoing, and resolved the matter to focus on its mission. It emphasised that the FTC did not challenge the core efficacy of its products including its use of AI, and pointed to incidents in which its scanners did detect guns students attempted to bring into schools.

THE CASE FOR IT

The problem is real and the alternative is unattractive. Metal detectors are slow, create queues that are themselves a vulnerability, and are experienced as prison-like in a school. A system that screens a thousand people quickly without emptying pockets addresses a genuine operational constraint.

The scanners do detect weapons. Documented interceptions exist, and neither the FTC nor this site suggests the technology detects nothing.

THE CASE AGAINST

The gap between marketing and performance is the issue, and it was established by a federal regulator rather than by campaigners. A 58% knife detection rate and zero firearms detected across a month of subway screening are not incidental shortfalls; they are the central capability failing.

The false positive burden inverts the value proposition. Eighty-five thousand laptop alarms is not a screening system, it is a queue with extra steps — and the remedies proposed reintroduce exactly the staffing and equipment the product was sold as replacing.

The most serious allegation is the alteration of a third-party test report. Independent evaluation is the only mechanism by which a purchaser can check a vendor claim, and interfering with it undermines the entire basis on which these decisions are made.

The consequences fall on people who cannot assess the claims. School districts spent $3.7 million, $2.5 million and $17 million respectively on systems they had no capacity to evaluate, and a student was stabbed with a knife the scanner did not detect.

WHAT IS NOT ESTABLISHED

Current detection rates for the deployed configuration, after the sensitivity changes, are not independently published.

How many customers exercised the cancellation right is not established.

The outcome of the SEC investigation reported in 2024 is not established here.

No independent evaluation comparing these scanners against metal detectors in matched conditions has been identified.