Washington Petition To Decide Parentage is a legal process in Washington state that allows a person to establish the legal parent-child relationship between themselves and a child. This process is available to parents who are not married, or who have never been married and have not established the parent-child relationship in any other way. The petition is filed in the Superior Court in the county in which the child resides and is usually decided by a judge. There are two types of Washington Petition To Decide Parentage: voluntary acknowledgment of parentage and court-ordered paternity. Voluntary acknowledgment of parentage is when both parents sign a declaration of paternity, which establishes the parent-child relationship. Court-ordered paternity is when a judge orders a paternity test to determine if the alleged father is the biological father of the child. If the paternity test results are positive, the court can then issue an order establishing the parent-child relationship.