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Can they be charged with a DUI? Or if they are in a crash That results in a death manslaughter?
Homer did you forget about mayfield?
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Can they be charged with a DUI? Or if they are in a crash That results in a death manslaughter?
Homer did you forget about mayfield?

I would think an aggressive prosecuting attorney would file charges.
Not a DUI because he is not on public roads and racing under the influence is not illegal but maybe manslaughter.
The answer is no. There is a difference between RULES in a competition and LAWS in public. Driving a race car while intoxicated violates a NASCAR rule, not a law. Break a rule, you deal with NASCAR and CANNOT be put in jail. Break a law, you deal with the police and prosecutors and COULD go to jail.
All of that is separate from a civil suit. Anyone harmed by a driver that was proven to have used drugs, could sue the driver and/or NASCAR for monetary damages only (no jail).
your funny
Usually they are tested before a race not after.