Ben Fox Rubin/CNET

Law enforcement agencies across the US are ordering a different kind of product from Amazon -- facial recognition.

According to documents and emails obtained by the American Civil Liberties Union, Amazon has been selling facial recognition technology called Rekognition to police. The tech, which Amazon boasts can track and analyze hundreds of people in a photo using a database with tens of millions of faces, has been used in Orlando, Florida, and by the Washington County Sheriff's Office in Oregon.

An Amazon Web Services spokeswoman said Rekognition isn't used for active surveillance, like Raju Das, the facial recognition software's director, said at the AWS Summit in Seoul.

In the clip posted May 1, he suggested that Rekognition could follow Orlando's mayor using cameras throughout the city.

The company defended its facial recognition program, which matches photos and videos uploaded by the customer -- not by Amazon. The AWS spokeswoman said it had been used to help find lost children at amusement parks, and was used for public safety at the Royal Wedding on Saturday to identify attendees.

"Our quality of life would be much worse today if we outlawed new technology because some people could choose to abuse the technology. Imagine if customers couldn't buy a computer because it was possible to use that computer for illegal purposes?" the spokeswoman said.

Facial recognition software isn't new for law enforcement, which often relies on technology to help with investigations. But facial recognition also has its flaws. For instance, reports found that software used by the UK's Metropolitan Police had incorrect matches in 98 percent of cases. Another concern with Rekognition is that it comes from Amazon, the largest online retailer in the world, which also happens to be staking a claim in smart homes through voice assistants and cloud cameras.

The partnering of massive tech companies with law enforcement efforts often strikes a nerve, raising concerns about privacy and software flaws. At Google, meanwhile, a number of employees have quit amid reports of a controversial military contract, Gizmodo reported last week.

The ACLU raised these issues with Amazon CEO Jeff Bezos in an open letter it sent Tuesday. The letter, signed by a coalition of organizations including the Electronic Frontier Foundation and Human Rights Watch, expressed worries about Amazon encouraging law enforcement to use the technology to monitor "people of interest," which could include undocumented immigrants and activists.

"Amazon Rekognition is primed for abuse in the hands of governments," the letter said. "This product poses a grave threat to communities, including people of color and immigrants, and to the trust and respect Amazon has worked to build."

ACLU

The Washington County sheriff's department has a database with 300,000 mugshots that it could yoke to Amazon's Rekognition, as well as a mobile app for deputies. Records show that Amazon charges about $1 for every 1,000 images scanned. One bill revealed that Amazon charged $33.95 for 277,461 images processed in a month.

Law enforcement agencies in California and Arizona also showed interest in Amazon's technology, the ACLU said.

First published May 22, 7:42 a.m. PT.

Update, 9:09 a.m. PT: To include statements from Amazon.

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