If you’ve ever had the misfortune of being pulled over, you’ll know the rising panic that ensues. Your mind starts to race with questions: How fast was I going? What have I done? When the police officer walks over to your car, you may have noticed that they almost always tap your taillight before they approach your window. Why do they do this?

Criminal behavior

There are several reasons for this seemingly odd habit, and the first is to foil the more hardened criminal. Police are never sure what they are walking into when they pull someone over. A criminal may be reaching for a weapon or beginning to hide drugs or evidence as the police approach. Officers will tap the taillight (or in some cases, tap on the trunk) to startle the driver, hopefully making them pause long enough for the police officer to approach.

Safety

The second reason is also related to safety. By tapping the taillight, the police officer is leaving his or her fingerprint on the vehicle. Should anything happen to them — an abduction, for example — there will be some physical proof that the police officer had been there.

Dash cams

The practice of tapping the taillight has fallen out of practice somewhat since the introduction of dash cams. In fact, some officers believe it could be dangerous to the their safety. Tapping the car can alert a dangerous driver to the location of the officer in the dark. But many law enforcement officers continue to do it. They reason that the startling tap can tell them a lot about the person behind the wheel. If the driver is overly surprised, it may be because they have something to hide.

What to remember

If this happens to you, don’t be concerned. Many police officers consider this standard practice. Always observe the speed limit, never drink and drive and hopefully, you’ll never need this information. If you do get pulled over however, remember to stay calm and polite — the police want to the situation to be over quickly as much as you do.

See Also: The reason those black dots are on your windshield

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