How does a cop know which car was speeding?

How do radar guns work? I got a speeding ticket. There were two other cars around me, so how did the cop know it was me who was speeding?

Phoebe Mah · Updated on
Reviewed by Shannon Martin, Licensed Insurance Agent.
When using a radar gun to catch speeding drivers, the fact of the matter is cops use their judgment to determine which car was speeding.
The technology behind radar guns is not perfect. The light beams are similar to flashlight beams in that they spread out the farther they travel. So, if you’re in a group of cars a decent distance away from the cop, there’s a high chance the radar gun may detect two or more cars at once when measuring the speed.
If all the cars in the pack were speeding, it may be a moot point—you were driving too fast. You just happened to be the unlucky driver who was pulled over this time.
In some states, radar guns are illegal. This is because they can be inaccurate in the ways specified above, as well as due to weather interference and issues surrounding faulty calibration.
The best thing you can do to avoid pricey tickets in the future is to be mindful of your speed.
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MORE: How long does a speeding ticket stay on your record?
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Jerry partners with more than 50 insurance companies, but our content is independently researched, written, and fact-checked by our team of editors and agents. We aren’t paid for reviews or other content.

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