Dear Slightly Creepy Old Man - I almost called the police on you a few months ago, and I saw you again a few days ago. I know that what you are doing is in good faith and is part of your need to fulfill your community responsibility. I assume that you are retired, so you are the right person for the job. But dear old man, slapping a magnetic sign on the side of your car that says ______ ________ Community Patrol does not allow you to drive slowly in the shoulder of the streets in thes semi-neighborhood, scoping out houses and creeping out the folks at home. I'm honestly not sure why you are doing this - we've lived here for over a year now and I've never heard that there was a neighborhood patrol, or even a neighborhood association (never even seen signs of it other than a Halloween party and a wine tasting more recently). Not sure if you are a paid employee, but I've seen the sign slapped on two different cars now, the first of which was facing away from the house and almost made me call the police.
So, if you are going to be the neighborhood patrol (which I don't think there's anything wrong with) you need to inform the residents that you are doing so, letting them know that you aren't just a creepy old man driving around with the sign slapped on your car. For all I know you could be looking at my house out to see when we are home and when we are gone, casing the joint to rob it in the future. Even a crime watch sign would be helpful - there aren't any in our immediate area that I've seen. And hten I'd know that you are there to protect me as opposed to scoping out my home.
Signed, Your Friendly Neighbor