(Bloomberg) -- Amazon.com Inc. drew the ire of the American Civil Liberties Union on Tuesday over a facial-recognition system offered to law-enforcement agencies that the advocacy group says can be used to violate civil rights.

In marketing materials obtained by the group, Amazon Web Services said its Rekognition system uses artificial intelligence to quickly identify people in photos and videos, enabling law enforcement to track people.

"Amazon’s Rekognition raises profound civil liberties and civil rights concerns," the group said in a statement. "Today, the ACLU and a coalition of civil rights organizations demanded that Amazon stop allowing governments to use Rekognition."

Law enforcement agencies in Florida and Oregon are using the service for surveillance, according to the ACLU. The group used public records requests to learn about the service.

Government use of facial-recognition software has raised concerns among civil rights groups that maintain it can be used to quiet dissent and target groups such as undocumented immigrants and black rights activists. Some AI software that’s used for facial recognition has been shown to be racially biased because it was trained using images with relatively few minorities included.

"When we find that AWS services are being abused by a customer, we suspend that customer’s right to use our services," Amazon said in an emailed statement. "We require our customers to comply with the law and be responsible when using Amazon Rekognition."

The company said "various agencies" have used Rekognition to find abducted people, without providing specific examples. Amusement parks use Rekognition to find lost children, while the recent British royal wedding used Rekognition to identify attendees, it added.

Oregon’s Washington County sheriff’s office wants to use the system to scan some 300,000 booking photos from its jail that it has compiled since 2001, according to records obtained by the ACLU.

A marketing presentation by Amazon’s cloud-computing business indicated the Rekognition system can slash the time it takes to identify individuals in photos and video surveillance. The company’s technology does it in minutes versus days when images are sent to different law-enforcement agencies for manual review, according to the marketing documents obtained by the ACLU.

In one email exchange last year, an Oregon law enforcement officer asked if the product could be enhanced to automatically tag inmate booking photos with descriptions of their tattoos. The system already tags a photo of someone with "tattoo," but the officer wanted to know if it could be enhanced to describe the tattoo with "dragon" or "flower" to make the tags more precise.

To contact the reporter on this story: Spencer Soper in Seattle at ssoper@bloomberg.net

To contact the editors responsible for this story: Jillian Ward at jward56@bloomberg.net, Alistair Barr, Emily Biuso

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