How do I win a no seat belt ticket ? The seat belt was on all the time. Trooper claimed it wasn't.?

this happened to my Wife. She was going to town and was pull over by a trooper. he asked why she did not have the seat belt on and it was on all along. She is steamed and so am I. her word against his so I guess she don't stand a chance. One more thing is that we had friends who witnessed her put it on before she left and was right behind her right up until the trooper cut them off to pull her over. He was angry and rude to her when he came to her window. He pulled her over as she was on her way to get a tag for the car we just bought. He was doing the limit and had insurance but no tag, She was on the way to get it .