There's a chance you've walked through a weapons scanner and didn't think much of it.
They're used at Wrigley Field, Soldier Field, inside Illinois schools and at big Chicago events like the Bank of America Chicago Marathon.
NBC 5 Investigates even found one inside the Chicago Police headquarters, although CPD has refused to say how they acquired it.
All of them are using AI-powered weapons detectors made by the Massachusetts-based company, Evolv Technologies, which has faced increased scrutiny in recent years over questions about the devices' efficacy.
A months-long investigation by NBC 5 Investigates found these scanners have limitations – and at times have failed to detect certain weapons.
- At a Utica, New York, school in 2022, the district canceled its contract with Evolv after a student was stabbed.
- Another stabbing incident happened at a Columbus, Ohio, high school in April of 2023, two months after the state's largest school district signed a $3 million contract with Evolv.
- A stabbing at a Buffalo, New York, school in mid-September raised more questions about how a knife could get through the scanners.
The devices do have sensitivity that can be adjusted by the end user.
But NBC 5 Investigates found Evolv was aware as far back as 2021 that its scanners could miss certain weapons.
During a YouTube video posted to its page, Evolv’s CEO publicly discussed the results of a 25-page report from a field test conducted at a Major League Soccer stadium in Columbus, Ohio. That 25-page report showed the Evolv Express weapons detectors performed relatively well, earning a score of 2.84 out of 3 by the third-party tester NCS4, the Nation Center for Sports Spectator Safety and Security, based at the University of Southern Mississippi.
But in a lengthier 52-page private report first obtained by the tech firm IPVM through a public records request, the results showed Evolv weapons scanners missed certain weapons. While it performed relatively well with most firearms, the testers noted that the Evolv Express failed to detect two micro-compact handguns during two pass-through attempts; had mixed results with metal pipes that could be used with explosives; and failed to detect knives 42 percent of the time.
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NBC 5 Investigates sent a records request to the University of Southern Mississippi but were told they would not release after releasing it to IPVM by mistake.
As part of a pilot program, the Evolv scanners were installed over the summer on the New York subway system.
Late last month, the New York Police Department released results that showed the scanners did not detect any passengers with firearms, but falsely alerted more than 100 times, according to data reported by our sister station, NBC New York. Through nearly 3,000 searches, the scanners turned up more than 118 false positives as well as 12 knives, the NYPD said, though they declined to say whether the positive hits referred to illegal blades or tools, such as pocket knives, that are allowed in the transit system.
Records obtained by NBC 5 Investigates showed mixed results at Rockford, Illinois, school district, which spent more than $2.4 million installing Evolv scanners at five district high schools.
While the district did detect five knives, there were hundreds of false positive alerts on laptops.
NBC 5 Investigates reached out to more than 400 school districts across the Chicago area and northwest Indiana.
More than 100 school districts responded to our survey. Approximately 8 percent said they were using weapons detectors, and more than half of that 8 percent said they were using Evolv.
We wanted to talk to Evolv executives directly, so we booked a flight to Orlando in late September to attend the Global Security Exchange conference.
We told an Evolv spokesperson we planned to attend. When we arrived, she informed us they would not be giving an on-camera interview. The reason we were given, according to Evolv's co-founder, was the ongoing investigations by both the Federal Trade Commission and the Securities and Exchange Commission.
According to SEC filings earlier this year, Evolv told its investors the FTC had questions about their marketing practices and that they had received a separate subpoena from the SEC.
As far back as 2022, Evolv marketed itself as creating a "weapons free zones" with "frictionless entry" – asserting that its devices could scan people faster and more efficiently than traditional metal detectors. But the company later backed off that phrase and switched to saying it created "safer zones."
Late last month, Evolv disclosed in another SEC filing that it had fired its CEO Peter George without cause – and separately – that some of its previously reporting sales figures were inaccurate and that "certain employees had engaged in misconduct in connection with sales that had 'extra-contractual terms and conditions' some of which were not shared with Evolv’s accounting personnel."
A spokeswoman for the FTC said they do not comment on investigations.
A spokesman for the SEC would not confirm or deny that they are investigating, but Evolv told its investors through an SEC filing earlier this year that it had been subpoena by the SEC and was cooperating.
NBC 5 Investigates reached out again to Evolv but have not heard back.
A rival speaks out
"Our detectors don’t cure cancer and they don’t read 'War and Peace' but they do that they are designed to do – they detect," said Luca Cacioli, the CEO of CEIA, one of Evolv’s chief competitors in the weapons detection industry.
During a sit-down interview with NBC 5 Investigates, Cacioli said the weapons detectors should be viewed and work best when they are part of a "layered-approach" to security. It's a refrain we heard over and over again during our visit, including from companies like Evolv.
The weapons industry is currently estimated to be worth more than $700 million, according to one industry estimate, but could blossom to more than $2.2 billion by 2033. We found three Illinois school districts had spent more than $4 million just since 2022 installing Evolv. As good as the booming industry is for innovators, Cacioli said, the industry is not strictly regulated.
“I think there is a dramatic lack of knowledge and questions being asked and testing - actual testing being done on what customers buy,” Cacioli said.
CEIA, which has its OpenGate detectors at Chicago City Hall and traditional magnetometers at the Chicago White Sox stadium, refers to the booming industry as the "wild west" because of what he calls a lack of regulation.
While several companies at the GSX conference mentioned that their products had the Department of Homeland Security’s Safety Act designation or certification, a DHS spokeswoman confirmed to NBC 5 Investigates that the federal government doesn’t actually test these devices. Instead, they rely on data from the companies themselves.
In response to NBC 5 Investigates’ questions, the spokeswoman sent this:
- The SAFETY Act process is a paper-based review that relies on effectiveness data submitted by the applicants. This data may include third party testing, end user data, or industry certifications. When appropriate, our office may also receive data and information from federal, state, or local government entities that use the technology. While we do not conduct our own testing, our evaluation relies on a broad swath of data, including test data to determine whether the technology is a capable and effective anti-terrorism technology, as required by the statutory criteria.
- With regards to endorsing products, there are ethics laws and regulations that apply to all federal agencies relating to conduct that creates improper appearances and endorsements. Our office, like all other federal agencies are bound by these ethics laws and regulations.
