When workers at an Ace Hardware here reported that a woman had walked out of the store with an $11.99 tank of welding gas that she hadn’t paid for in her tote bag, an elaborate high-tech crime-fighting operation sprang into action.
A Washington County sheriff’s detective, working with the agency’s Special Investigations Unit, ran the store’s surveillance footage through an internal facial-recognition program built by Amazon, revealing a possible match. That woman’s license plate was flagged and, three months later, a narcotics officer in an unmarked SUV saw it and radioed other patrol deputies to stop her. A deputy clapped a pair of handcuffs around her wrists, an arrest report states. She said she’d needed the gas to fix her car. Deputies in this corner of western Oregon outside ultraliberal Portland used to track down criminals the old-fashioned way, faxing caught-on-camera images of a suspect around the office in hope that someone might recognize the face.
Then, in late 2017, the Washington County Sheriff’s Office became the first law enforcement agency in the country known to use Amazon’s artificial-intelligence tool Rekognition, transforming this thicket of forests and suburbs into a public testing ground for a new wave of experimental police surveillance techniques.
Almost overnight, deputies saw their investigative powers supercharged, allowing them to scan for matches of a suspect’s face across more than 300,000 mug shots taken at the county jail since 2001. A grainy picture of someone’s face – captured by a security camera, a social media account or a deputy’s smartphone – can quickly become a link to their identity, including their name, family and address. More than 1,000 facial-recognition searches were logged last year, said deputies, who sometimes used the results to find a suspect’s Facebook page or visit their home.
But Washington County also became ground zero for a high-stakes battle over the unregulated growth of policing by algorithm. Defense attorneys, artificial-intelligence researchers and civil rights experts argue that the technology could lead to the wrongful arrest of innocent people who bear only a resemblance to a video image. Rekognition’s accuracy is also hotly disputed, and some experts worry that a case of mistaken identity by armed deputies could have dangerous implications, threatening privacy and people’s lives.
Some police agencies have in recent years run facial-recognition searches against state or FBI databases using systems built by contractors such as Cognitec, IDEMIA and NEC. But the rollout by Amazon has marked perhaps the biggest step in making the controversial face-scanning technology mainstream. Rekognition is easy to activate, requires no major technical infrastructure and is offered to virtually anyone at bargain-barrel prices. Washington County spent about $700 to upload its first big haul of photos, and now, for all its searches, it pays about $7 a month.
It’s impossible to tell, though, just how accurate or effective the technology has been during its first 18 months of real-world tests. Deputies don’t have to note in arrest reports when a facial-recognition search was used, and the exact number of times it has resulted in an arrest is unclear. Sheriff’s officials said the software has led to dozens of arrests for theft, violence or other crimes, but a public-records request turned up nine case reports in which facial recognition was mentioned.
“Just like any of our investigative techniques, we don’t tell people how we catch them,” said Robert Rookhuyzen, a detective on the agency’s major crimes team who said he has run “several dozen” searches and found it helpful about 75% of the time. “We want them to keep guessing.”
Sheriff’s officials say face scans don’t always mark the end of the investigation: Deputies must still establish probable cause or find evidence before charging a suspect with a crime. But the Sheriff’s Office sets its own rules for facial-recognition use and allows deputies to use the tool to identify bodies, unconscious suspects and people who refused to give their name.
The search tool’s imperfect results raise the risk of an innocent person being flagged and arrested, especially in cases of the scanned images being blurred, low-quality or partially concealed. Deputies are also allowed to run artist sketches through the search, an unusual use that AI experts said could more often lead to a false match.
Amazon’s guidelines for law enforcement say officials should use Rekognition’s results only when the system is 99% confident in a match. But deputies here are not shown that search-confidence measurement when they use the tool. Instead, they are given five possible matches for every search, even if the system’s certainty in a match is far lower.