Criminal law, traffic matters, DUI, assault, theft, fraud
It may have been overlooked, back then most things were recorded on paper, if it was misfiled it may have only just turned up. A warrant is a warrant, if it's valid they can act.
But what do you remember of the event, did it happen, were you picked up for driving under the influence or is it mistaken identity?
If you have had a clean record since you have a good case for perhaps just receiving a rap over the knuckles rather than loosing your license, see a solicitor to get assistance in achieving this.