Had an interesting run in with the police today.
A cop pulled me over as I was on my way to get my allergy shots. He told me that the car I was driving wasn't the one that was registered to those plates, and one or the other might be stolen. I explained to him that I had just bought this car last week and had transferred the plates from my old car to this one. Apparently the DMV is just really bad at updating their records in a timely manner. I showed him the new registration with the current car and plates and he said everything was fine.
Then I asked him why he ran my plates in the first place and he told me he had a system in his car that automatically scanned all nearby plates and pulled up all relevant info as well as any potential red flags. It told him the car was supposed to be green, when it was actually blue (the old car was green). I'd never heard of such a thing before today, so I looked it up. It's called an Automated License Plate Reader (ALPR). I have mixed feelings about this. In my case, I was early enough that being pulled over didn't make me miss my appointment. But that could easily have not been the case. I wasn't doing anything even remotely illegal, yet I still got stopped anyway.
I can see how this could be used to track a person's driving habits, and there are plenty of people who would consider this an invasion of their privacy. And I can't say I disagree.