Make the appearance date, and if you can hire an attorney that specializes in traffic ticket defense. There are likely several ways to challenge the ticket and it's possible that the officer had a dash camera. If he did, that will show one of a few things- either it's not possible for the camera (or the officer) to tell whether you wearing the belt, that you were wearing the belt or that you weren't. Either way, you have a witness and should challenge the ticket if you believe you are innocent.
Good luck.
If you challenge the ticket, they have to give you a trial in front of a Judge. It is possible you might have some success. However, a seat-belt ticket does not count as points against your driver's license or raise your insurance rates. It therefore becomes more of a cost-benefit analysis-- you will have to wait a long time in court, take more time doing the trial, possible additional cost of hiring an attorney, etc. It's worth it to some folks, but not to others.
If it is only a seatbelt ticket then it is not worth fighting. Just pay it off. There are no insurance points or license points for this. Also, the ticket cost will not be much more than $100, so why would you want too hire a lawyer or miss work for that???
