SPERS is a registery which the DOT and cops give their tickets to when you don't pay it by the due date so it can be followed up. Spers adds a $40 fee to it and sends you letters to pay. As far as I know, unless the fine is of a large amount (>$500) they don't usually harrass you.
However, if you didn't do it, it would be good to get it cleared.
Why is it that all the reject cops get stuck on road patrol and break & enters?