I am not licensed to practice law in Ohio or Michigan, but it is my understanding that all states share information regarding traffic violations. So, if your son pleads guilty, it is very likely that Ohio will report the speeding conviction to his home state of Michigan. You should contact the state agency in Ohio that regulates driver's licenses to ask how Ohio will treat your son's speeding ticket to find out if they will report it to Michigan. Then contact the state agency in Michigan that regulates driver's licenses (Dept. of Motor Vehicles?) and ask how they will treat an out-of-state speeding conviction.
My advice is for your son to hire a criminal defense attorney or traffic law attorney in the city or county in Ohio where your son received the ticket to have the attorney negotiate a plea bargain with the prosecutor to get the speeding ticket reduced to a non-moving, no-point infraction. If his ticket does get reduced to a non-moving infraction, then most likely it won't be reported to Michigan.
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