@Joe,
If you do not pay, chances are you will be hit with yet another fine, a more expensive fine. If you do not pay the second, you may face a third or even a few nights in jail.
Simply refusing to pay the fine is about the worse thing you can do. Refusing to pay the fine will only invite greater legal trouble.
If you take issue with the fine, a letter to the judge sounds like a good idea, or you could go to court on your assigned day and contest the fine.
"In a closed society where everybody's guilty, the only crime is getting caught." Looks like your Dad got caught.