I take pride in saying that I have never been pulled over before. Parking tickets? Absolutely. But speeding or distracted driving? Never. But from what I hear, it can be a pretty scary experience. Most people are nervous when officers gesture them to pull over, which is fair. I can't think of the last time someone got pulled over so a cop could congratulate them on their good driving skills.
If you have been pulled over, you may have noticed that the officer will often tap on your trunk or back taillight before approaching your window. Many assume this is an intimidation tactic to make the driver more uncomfortable, but there are actually two reasons they do it!
The first reason is fairly basic: they want to make sure you're not trying to hide anything. Most people try to hide drugs or weapons when pulled over by a cop, expecting to only see the officer at their window. But if there's a tap on the taillight, criminals are more likely to panic and disrupt their process. This can make it easier to catch them involved in illegal activity.
Sounds pretty basic, right? Just a run-of-the-mill tactic to assert your dominance. However there's another, much more serious, reason that officers will tap your taillight.
Before the invention of dash cams and body cams, officers had no way of proving an encounter. By touching the taillight of a vehicle, they were able to leave behind evidence of them being there by way of a fingerprint. If something happened to the officer during the stoppage, the car could be traced back to the fingerprints left on the taillight. Even without video proof, a suspect could be tied to the disappearance of an officer due to the prints.
Now, however, police departments advise against this tactic. The belief is that tapping the taillight can give away an officer's location, which could be dangerous in the event that the person they've pulled over is dangerous. It's also pretty unnecessary, considering all the technology they have in their cars now. That being said, a lot of officers feel like they need to tap the taillight or trunk as a superstition. It makes them feel safer and keeps them in a routine.
I would have never guess this is why police officers tap taillights, but I guess you learn something new every day, right?