Why the American Civil Liberties Union is calling out Amazon's facial recognition tool, and what the ACLU found when it compared photos of members of Congress to public arrest photos. Facial-detection technology that Amazon is marketing to law enforcement often misidentifies women, particularly those with darker skin, according to researchers from MIT and the University of Toronto. Privacy and civil rights advocates have called on Amazon to stop marketing its Rekognition service because of worries about discrimination against minorities. Some Amazon investors have also asked the company to stop out of fear that it makes Amazon vulnerable to lawsuits. The researchers said that in their tests, Amazon's technology labeled darker-skinned women as men 31 percent of the time.

Matt Wood, general manager of artificial intelligence with Amazon's cloud-computing unit, said the study uses a "facial analysis" and not "facial recognition" technology. Wood said facial analysis "can spot faces in videos or images and assign generic attributes such as wearing glasses; recognition is a different technique by which an individual face is matched to faces in videos and images."