Pulled over and ticket issued by GSP for no helmet in Georgia

Wife got pulled over and issued a ticket for no helmet in the Slingshot by GSP, mind you shes been pulled over atleast 5 times already and never a word about a helmet (They pull her over because shes a young blonde and they just want to see the vehicle). We have over 3,000 miles on it. He said he had a superior with him or something and had to. I didn't get there in time to discuss the law with him, but the law exempts helmet use for anything with an enclosed cabin. I would say its as much or more of an enclosed cabin as a Jeep is. She said he was real nice and that he didn't think it looked like you needed a helmet, but told her to go to court and he will show up and actually help here get out of it. Said he wants to buy one and wants the law to be clear for no helmet use in it. He also said she wont have to pay it if she shows up after they take a look at the vehicle. Sounded sure of it, but sounds a little funny to me but we'll see. Now I know some of you may not condone no helmet use, but I really don't want to always have to wear a helmet. I have only been wearing one on the interstate. The SS is just not quite as much fun with a helmet on, and I'd honestly rather take the risk if there is one.

If anyone can offer key points in any of the laws that would help the case, please share. Let's get the SS in the books.