if you watch a policeman walking towards you in the review mirror, you may notice he will suddenly stop and touch your taillight.
Why do cops do that? It may seem like just a little tap, but when an officer touches a taillight, it has more meaning than most people realize.
A policeman touches the rear lights because it leaves behind evidence, and lots of it! Cameras weren't always as inexpensive as they are now. That meant most police departments couldn't afford to equip all their cruisers with a camera. Touching the taillights or the trunk meant that officers had forensic backup.
It's kind of like a dog marking his territory, but cops leave their mark as a safety precaution - just in case! If the officer is attacked or happens to disappear, then his fingerprints could be used as proof that the car was somehow involved.
These days, most police cruisers come equipped with cameras, so it's not necessary to leave fingerprints all over the place. Plus, car washes have become just as popular as dashboard cameras! Yet, some old-timers are still in the habit of tapping the taillights. In the end, it's probably just a superstitious ritual that helps them feel safe.
However, some police departments are advising against this outdated ritual. In the dark, a taillight touch could "give away" a policeman's position and make him an easy target, especially if any of the occupants are carrying a loaded weapon.
But, should your taillights get a good thumping the next time you get pulled over, at least you know why. You could even turn the tables around, and try to startle the police officer with your questions about the practice. Maybe he'll get so distracted with your insider knowledge that he forgets to give you a ticket!