Why Does a Policeman Touch a Tail Light?

Drivers involved in a traffic stop may witness law enforcement touch their car's tail lights instead of heading directly for the driver's side window to question the vehicle operator. This practice is decades old and completely legal. Cops do this for various reasons; it can tell them a lot about the driver and their vehicle and leaves evidence of their presence in the event of danger. However, as digital technology becomes more widely used, there are more accurate ways for officers to gather information and record evidence in the modern era.

Each time law enforcement pulls a driver over, they don't know what they might face. That person may carry a weapon, possess drugs or show impairment. When an officer approaches, a driver involved in a nefarious activity may attempt to hide whatever contraband or prohibited items they have in the vehicle before the officer can get up to the window.

When an officer taps the tail light, it may startle that motorist from their momentary goal of hiding criminal evidence and give the officer the opportunity to witness their ruse. According to The Law Dictionary, this practice has shown success in increasing arrests of impaired or intoxicated drivers, sellers of prohibited substances and those in possession of unlicensed firearms or involved in other offenses.

Touching the tail light can serve as evidence for an officer in a vulnerable situation. In decades past, an officer touched a driver's tail light at a traffic stop to leave fingerprints somewhere on the car. This would prove that they were at the scene in the event they were injured or killed in the line of duty. When a criminal investigation occurred, this could serve as evidence; if a vehicle were particularly dirty, the officer's fingerprint would also stand out.

However, this old-school practice wasn't always definitive, as fingerprints are easy to tamper with or smudge. They can also wash away in wet weather. The noise from the tap exposed law enforcement's position, potentially making them susceptible to attack. Today, there are better, safer and more definitive ways to secure evidence at a traffic stop.

A police offer approaching a vehicle may believe they are in a dangerous situation and touch the back of the car to check for an open trunk latch. Doing this ensures that no one will pop out and unexpectedly cause them harm.

In many instances, police officers will have a partner with them during a traffic stop. One officer checks the back of the vehicle as the other approaches the driver's side window. Doing this with a partner further ensures their safety and diminishes the opportunity for the driver to hide anything or to grab a weapon.

According to Considerable.com, if a police officer touches a tail light today, it is more out of habit than for any other reason. Law enforcement now relies on digital technology when pulling someone over. Security cameras are everywhere, and cops rely on the dash cams in their police cars or on body cams for proof of what occurred. These record live video from all angles and eliminate the need for tail light tapping.

Some police departments discourage officers from this practice, as it could put them in unnecessary danger. Departments may tell them to touch only the side of the vehicle, not the back, as doing so could reveal their position and put them in grave danger if a driver decides to put the car in reverse. No matter what they do, officers continue to practice preparedness for any outcome as they approach a vehicle during traffic stops.