What Happens If Paternity Test Results Are Inconclusive?
An inconclusive or challenged paternity result is not the end of the road. Washington law anticipates that first-round genetic testing will not always settle the question, and it builds in clear next steps for getting to a reliable answer. The Law Office of Chad Foster helps Snohomish County families with parentage matters. First confirm how legally valid genetic testing for paternity works.
What "Inconclusive" Actually Means
People often say a paternity test is "inconclusive," but it helps to understand what that means in legal terms. Washington sets a precise standard for when genetic testing actually identifies someone as a genetic parent. Under RCW 26.26A.325, a person is identified as a genetic parent only when the testing shows at least a ninety-nine percent probability of parentage, using a prior probability of 0.50, together with a combined relationship index of at least one hundred to one. If the results fall short of that threshold, the test has not identified the person as a genetic parent. In everyday language, the result did not reach the level of certainty the law requires, which is often what people mean when they call a result inconclusive.
A result can also come out clear on its face but still be disputed. Someone identified as a genetic parent may believe the result is wrong, or a party may question how the sample was handled. Washington treats a challenge to a result and a result that fails to meet the standard as related problems with the same solution: test again, correctly.
Additional and Repeat Testing Is Available
The most important thing to know is that the law gives you a right to further testing when you contest a result. RCW 26.26A.335 provides that the court or the child support agency must order additional genetic testing when an individual contests the result of the initial testing. There is a practical condition attached: if the initial test already identified someone as a genetic parent, the person contesting it has to pay for the additional testing in advance. That rule discourages endless retesting for its own sake while still guaranteeing a second look to anyone who genuinely disputes the outcome. A disputed result can also require a court proceeding to resolve parentage.
The statute governing challenges, RCW 26.26A.325, adds an important detail about how a person who has been identified as a genetic parent can fight the result. That person may challenge it only through more genetic testing that meets the same reliability requirements, and that testing must either exclude them as a genetic parent or point to another possible genetic parent. In other words, the way to overcome a scientific result is with better science, not argument alone.
When More Than One Possible Parent Appears
Sometimes testing does not fail so much as it produces a complicated picture. If genetic testing identifies more than one individual, other than the woman who gave birth, as a possible genetic parent, RCW 26.26A.325(3) directs the court to order each of those individuals to submit to further testing to sort out who the genetic parent is. The law also addresses an unusual but real scenario. Under RCW 26.26A.350, if there is reason to believe an alleged parent has an identical sibling who might be the genetic parent, the court can order the sibling to be tested too, because identical siblings can produce overlapping genetic results. When that happens, the court may rely on non-genetic evidence to decide which sibling is the parent.
Making Sure the Testing Was Done Right
Before assuming a result is simply inconclusive, it is worth confirming that the testing met Washington's quality standards, because a flawed test is a fixable problem. RCW 26.26A.315 requires that genetic testing be of a type reasonably relied on by experts and be performed in a laboratory accredited by the AABB or another approved accrediting body. RCW 26.26A.320 requires a signed report and documentation establishing a reliable chain of custody, meaning a clear record of who collected each sample, when, and who handled it. If the chain of custody is broken or the lab was not properly accredited, that alone may justify redoing the test. RCW 26.26A.315 also allows a party to object, within thirty days after receipt of the report, to the ethnic or racial database the lab used to calculate the results and to request a recalculation, which can matter when the underlying statistics affect the outcome.
Practical Next Steps
If your result came back inconclusive or you believe it is wrong, the path forward usually involves a few things. Read the actual report, not just the summary, and check the probability figures against the statutory threshold. Confirm the lab's accreditation and the chain of custody. Decide whether to request additional testing under RCW 26.26A.335, keeping in mind who bears the cost. And consider whether an issue like an untested sibling or a database objection applies to your case.
A Snohomish County Perspective
For families in Everett, Lynnwood, and across Snohomish County, getting parentage right matters for child support, for parenting plans, and for a child's sense of identity. An uncertain first test can feel discouraging, but the framework is designed to keep working toward a dependable answer rather than leaving families stuck.
Every situation is different, and this article speaks in general terms rather than about any specific case. If your paternity results came back inconclusive or you want to challenge a result, the Law Office of Chad Foster can help you understand your options and next steps. Reach out to talk it through.
Need help with a child custody or support matter in King or Snohomish County? Learn about our child custody and support services, or call 425.785.8679 for a consultation.