Contempt in Washington is governed by RCW 7.21. It is the willful violation of a court order. In child support, contempt is meant to be coercive, that is, to get you to do what you already are able to do. Courts really just want for paying parents to get employed and make their payments. To get started, you have to use the court forms from the state court website (linked below). If your child support goes through Division of Child Support, you can go to your DCS office and get a "Case Payment History." Try to get a certified copy. If they don't give you a certified copy, that's okay. Keep the focus of your papers on the fact that the other person was court-ordered to pay X amount every month and hasn't. Going into emotional stuff about how you and the child are impacted doesn't help. It's not a punitive system. It's only about math.
Getting the Other Party into Court
The court has the power to incarcerate a parent on contempt as well as to order a new payment plan. If you are going to ask that the court to put the other person in jail, then you have to make sure the other person is personally served with the Order to Show Cause on Contempt. Make sure the process server gets the Return of Service filed! When the case is first in front of the court, the court may give the other party a chance to be screened for a public defender. Counties handle contempt public defense differently. All you need to know is that your first court date may well get continued. Don't let any hearing get continued without the continuance order specifically stating that the if the other party doesn't show up for court, then a bench warrant for his/her arrest may be issued. Make sure the other parent him/herself signs the order!
The Contempt Hearing
At the actual hearing on the merits, keep your focus on the money. Ask for a judgment for the money owed, the $100 Civil Penalty, and for reimbursement for the process server in addition (of course) for a finding of contempt. The court will NOT find contempt if the other parent is on Social Security Disability, VA disability (with a high disability rating), GAU, TANF, L&I or unemployment. Unemployment and L&I have their own formula for how much benefits get paid to child support. The other parent has no control over it. The fact that there should have been a modification of child support is not a defense against contempt. When the contempt hearing is over, ask for a review hearing especially if the other parent was given a chance to make payments instead of immediately going to jail. Just before a review hearing, provide the court with an update in writing of what payments you've received as well as a new Case Payment History. You can ask for jail at a review hearing.
The parent will be ordered to pay support plus an amount on back support. There's many ways to handle back support. For example, work out the taxes with you claiming the kids and then with the other parent claiming them. If there's a bigger refund with the other parent claiming, then let them do so. Because there's back support, the refund will go to you on back support anyway. If the children are within 4 years of emancipating, set back support low with the provision that as each child emancipates the amount paid each month stays the same. As each child emancipates more and more of the monthly payment goes to back support. The paying parent gets the benefit of one amount that won't go up or down. If the back support is all owed to you (meaning you were never on public assistance) you can compromise the debt too. This happens when the paying parent inherits a chunk of money that covers most of the back support. Once you forgive any part of the debt, you can't go back for it.