https://arstechnica.com/tech-policy/2017/09/what-you-should-know-about-privacy-and-apples-faceid-on-ios-11/

During and after yesterday's Apple announcement of its FaceID unlocking feature for its new iPhone X, some brief discourse began on the Ars #staff Slack channel concerning legal rights when your face is your new passcode. It's a big deal, as this is the future of smartphone unlocking—largely because Apple says so.

"This is the future of how we'll unlock our smartphones and protect our sensitive information," Apple VP Phil Schiller said.