Re: facial recognition
"In the UK the police can hold you without charge for a period (24 hours minimum, more in relation to some crimes) and have no obligation to tell you why, or to answer your questions."
True, but they have to have, when challenged, good reason to believe the person has committed a crime. If you arrest some guy who doesn't look like a picture, even if an eyewitness pretends it is them, that doesn't =count. Look at the photo, look at the person standing in front of you.
The same is true in the US. Hence the lawsuit.