There's a whole section of law that determines when the police are able to take DNA samples or fingerprints, and more laws for how long they can keep that information.
It's regulated. And bringing face recognition under biometric regulation is a no-brainer.
I think a lot of people down voting this need to read it again. They're not saying you should go faster because someone is close behind, they're saying go slower.
If they're 5m behind you, the safe speed is 20. If they're 2m behind you the safe speed is 10. (Numbers pulled out of my hat).