KK1, if I were you, I will pay for those US tickets especially it was from WA.
An unpaid traffic ticket could result into a warrant out for your arrest in that state. And when you cross the border as a driver, they will know it right a way. At least that's what I heard.
If you don't plan to drive down to the state again, then there is no worry.
myversa, did you pay for us traffic fine?
i've gotten few us speeding fines many years ago but haven't paid for. i just wonder how long the fines will be kept in the police record