lots of answers here..
Could be they use radar.. and V1 only goes off when the laser is fired at you or hopefully the car in front of you.

Any way you slice it, I am banking, they were not using any anti-speed devices when they passed you. Otherwise, your V1 would have told you.
Maybe they were on their way to a seminar, conference, etc.
Not all troopers do traffic stops either.

Don't worry, your V1 is fine.
B

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