You have been misinformed. To comply with the seat belt law a driver must secure the seat belt in position around his or her lap and shoulder BEFORE putting the vehicle into forward or backward motion.
Because you did not do so, (parking lot, gas station, church drive etc.... or other) you broke the law and could be cited.
There are statutes (laws) and caselaw (opinions by the Court of Appeals or Michigan Supreme Court) that hold that Operating While Intoxicated in parking lots and other places open to traffic is still illegal. However, the exact wording of the statute for seat belts in MCL 257.710e (3) states "Each operator and front seat passenger of a motor vehicle operated on a street or highway in this state shall wear a properly adjusted and fastened safety belt ..."
You state you were clicking your belt before entering the roadway. You were not on a street or roadway. But what will the officer say?
As you can see, there is nothing in the law about wearing the belt before starting the car. I can see that there might be an issue with distraction by having to fool with the belt while moving.
If it was me, I would ask for a hearing, state the facts, quote the statute, and ask the court to dismiss. On the other hand, will it be worth the time you spend fighting the ticket? What if the officer says you were on the roadway? What do you have to lose by trying the case? Well, perhaps half a day's work.
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