If you have the time to contest it couldnt hurt maybe get the fine reduced or eliminated
Around here, once in court judge can impose a fine up to $100 (I think) at their discretion even if it exceeds the standard fine for the offense. For many years that amount exceeded most traffic violation fines. Only in later years have they been going up and that $100 may have been increased too.
Anyway it was pretty routine for judges, on any challenge, if the judge found guilty anyway to impose the $100 fine as punitive response for challenging the violation.
If there is some lesser violation to "plead" down to it seems easier to get the prosecutor to do that but seat belt? What do you go down to?
Pay it and fix the belt. It's not worth wasting your time on fighting it.
I tend to agree, not worth the effort. Though sometimes the record of violation could show up undesirable ways. Like if someone was negligent in their driving struck you, caused some disability to you, even if you had your seat belt on, it might not be noted in the police report and this record of not wearing a seatbelt gets pulled into the mess. You are almost better off with a violation on record of missing plate than something relating to safety.
It seems to me that your only basis for contesting the ticket, and part of the questions, is if a seat belt violation is a secondary offense that can only be issued if stopped for another violation, because no other violation was issued, it isn't valid to issue this ticket. I don't know the law there so can't comment if any merit, but I am going to guess the officer covered himself by justifying the stop on the basis of not seeing a front license plate. It is entirely possible he saw the seat belt violation and intentionally didn't see the license plate to justify the stop.
Years ago I tried challenging a "failure to stay in lane" issued to me for having crossed a double yellow line. My defense was easy and logical and didn't dispute any facts. I had to cross the double yellow line to avoid ice in my lane, children on the right side of the road (by the ice), 200ft visibility (at the low speed I was moving) to know no risk from oncoming traffic. It was the prudent thing to do. The police officer had come around the corner up ahead as I was moving back into my lane, he was well over 150ft away, I was past the kids so he wouldn't have necessarily connected that with why I was there and ne hadn't given me an opportunity to say anything when he stopped me. Just asked for license, walked away, came back with ticket.
And you know what happened in court? The police officer flat out lied. He made a total tale of fiction. Claimed that I was also speeding, that I was begging him to cut me a break, that my being over the line was on the turn of the road rather than a strait section, that I had forced him completely off the road on the turn. That I was totally unprepared for and what I had to say made no sense in that context he created by his testimony and the judge of course imposed the bigger fine for such a terrible safety hazard I caused.