Information about Pierce County Courts is public. You can access it online. Type the correct information about your prospective employee in the search window and ask for a search using the appropriate dates.
This will give you information about arrests, no-contact orders and jail time in Pierce County during that time period.
Contact the Washington State Patrol to get a Washington State background check. You can actually do a background check over the internet if you are willing to put in a credit card number (it costs $10) or you can complete a form and mail it in with a check for $10.