I am not sure why this comment was marked dead without any responses, and hence I am "vouch"-ing for it. Can someone point to laws related to license plate tracking?

It seems to me that having a huge database of known locations of vehicles could be used to do some cool (but likely immoral) things, specially coupled with the fact that several state agencies all over the world make it free and easy to retrieve licensing and ownership information for vehicles. It'd also be relatively much easier to do compared to facial recognition.