First, you have the file a written motion to seal with the proper court and request a hearing. The proper court is the court in which your case was heard.
Second, you have to notify the prosecutor's office. You will also have to notify the crime victim (if applicable).
Example: The State charged you with assault in the fourth degree for allegedly punching your ex-boyfriend but Pierce County prosecutors ultimately dismissed the case. Several years later, you file a motion to seal your court records relating to this case in Pierce County District Court.
You are required to notify both the Pierce County prosecutor's office and your ex-boyfriend in writing. If you can't find him, you will have to prove that you exercised due diligence in trying to find him (i.e. tried to find him on social media, emailed friends and relatives, called last known numbers).
Third, if you are on probation, you will have to send a copy of your motion to the probation department. You will also have to notify the Department of Corrections (DOC) if you are under DOC supervision.
Who can file a motion to seal court records?
Not surprisingly, you can file a motion to seal your own court records. But under GR 15 (the applicable court rule), any "interested person" can file motion to seal your court records. Under Washington law, an “interested person” is someone who has a direct financial interest. This could be, for instance, the victim of an assault case or your power of attorney if you were incapacitated.
Do I need an attorney to get my court records sealed?
Getting your record sealed is a difficult hurdle, and the law is pretty technical.
Of course, with enough reading and research, you may feel comfortable filing a motion to seal by yourself. But you need to consider whether you're willing to risk making a mistake when so much is on the line.