They can get your criminal record if they want to by just communicating with the prosecuting district. Hell, I can go online now and tell you all the convictions EVER in my county.
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They will only check or have access to what ever you tell them Plus your motor vehical records which are kept by your states DMV.
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when they run a background check, they will find it. Don’t lie about it. And just to let you know, it will ALWAYS be on your record. It’s BS about when you turn 18, civil offenses, and dismissed charges.

A cop brought up a civil offense I did at 16 when I was 20.
I was told my civil offense (at 20) would be off my record in a year if I didn’t mess up. Well, it’s been longer than a year, and it’s still on my record.
If you had a drunk driving charge dismissed, and were caught drunk driving years later, they will use that against you in court.

They say it will be gone, so you’ll admit to it. Never trust a cop. Read your rights, especially if you plan on breaking the law. If you don’t know your rights, you will get effed.
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Good luck?
Bad luck!
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You can compare how the insurance quotes would change, for example here - autoinsurance.maclenet.com
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