Washington doesn’t have common law marriage. What it has instead is a court-made rule called the committed intimate relationship, or CIR, which lets a judge divide the property an unmarried couple built together. This post is part of a series on how that rule works. It answers one question: whether the rule can apply when your partner was still legally married to someone else.
Yes, it can. A committed intimate relationship with a married person is possible under Washington law. But the marriage makes the case harder in two specific ways. It cuts against the intent factor, because a court has to find that both of you intended a committed, marriage-like relationship, and someone who stayed married is arguing against themselves. And it can cut against the cohabitation factor if your partner was still living with their spouse for part of the time. The cases that succeed are the ones where the marriage was over in every way except the paperwork.
What the Supreme Court said about a committed intimate relationship with a married person
The leading case is In re Marriage of Pennington, 142 Wn.2d 592 (2000), which decided two cases together and found no CIR in either. In the first, the man remained married to someone else for the first five years of the relationship, and after his divorce he refused to marry his partner. The court held the doctrine “contemplates the mutual intent of parties to be in” a committed relationship, and the intent wasn’t mutual. 142 Wn.2d at 604. In the second, the woman was married, though separated, when she began dating her partner, and the court found the facts on intent “too equivocal” to support a CIR. 142 Wn.2d at 606.
Read those two results carefully. The court didn’t say a married partner can’t be in a CIR. It said the other facts in those cases didn’t show a mutual commitment. When one partner keeps a spouse, refuses to marry when free, or keeps a foot in both households, the court reads that as a lack of commitment, and no amount of time together fixes it.
The case that went the other way
In In re Long and Fregeau, 158 Wn. App. 919 (2010), one partner stayed married to someone else during the relationship, and there was infidelity on top of that. Division III still upheld the CIR. The court held that remaining married “is a fact to consider, but it is not determinative,” and that infidelity is weighed but doesn’t defeat the purpose or intent factors by itself. What carried the case was everything else: they lived together, planned a future together, and held themselves out as a couple. The court treated the marriage as a fact in the mix, not a bar.
In re Marriage of Byerley, 183 Wn. App. 677 (2014), is another example. When the couple reconciled after a break, one partner was married to someone else and already in divorce proceedings. The court found a CIR from the date they started living together. His marriage affected the timeline, not the result.
Where the marriage really hurts: cohabitation
The bigger problem is usually not the marriage certificate. It’s where your partner slept. Under the published rule, a CIR can’t begin before the couple starts living together. Byerley, 183 Wn. App. at 689. A partner who’s still living with a spouse and spending nights with you isn’t cohabiting with you in the way the cases require.
An unpublished 2025 Division I decision, Jorgensen v. Sears, is the clearest recent example. The woman was still married and living with her husband when the relationship started, and the couple’s time together was overnight stays. The court held those stays weren’t cohabitation, so even if a CIR existed it began no earlier than the date they started living together full time, after her divorce and after she’d bought her condo. By then there was no community-like property to divide, and the case was dismissed. Unpublished decisions don’t bind other courts, but Division I hears Snohomish and Island County appeals, and this is how it read the rule.
So the practical question is when your partner actually left the marital home and moved in with you, or you with them. That date, not the divorce date, is where a court is likely to start counting.
Your partner’s spouse may have a claim too
There’s a property problem on top of the proof problem. In Washington, what a married person earns or acquires during the marriage is community property of that marriage until the spouses separate and live apart. If your partner hadn’t separated from their spouse, the spouse may have a legal interest in the same wages and property you’re claiming a share of. That can put three people’s interests in one house or one account. It doesn’t defeat your claim, but it changes the strategy and sometimes the parties. Raise it with your lawyer at the first meeting.
What makes the case work
Show that the marriage was over in substance. Evidence that your partner and the spouse lived apart, when they separated, whether the divorce was filed and when. Then the forms and messages where your partner presented you as their partner while still legally married: insurance enrollments, emergency contacts, joint leases, how they introduced you to family and coworkers. Add the pooling records: joint purchases, shared bills, a down payment from both of you. And evidence of what your partner said about the future, in writing if you have it. The court is looking for mutual commitment. A married partner has to be shown to have made one.
Two things you can do now
Pin down the separation date in your partner’s marriage. When did they move out from the spouse? Is there a separation agreement, a divorce filing, a lease in your partner’s own name? That date is likely the earliest your relationship can count from.
Collect what your partner said about you. Texts, emails, and forms where they called you their partner, named you as a beneficiary or emergency contact, or planned a future. Mutual intent is the factor the marriage attacks, and this is the evidence that answers it.
Common questions
Can you be in a committed intimate relationship with a married person in Washington? Yes. The Court of Appeals has said remaining married is a fact to consider but not determinative. The relationship still has to meet the other factors, and mutual intent is the hardest one to show when one partner kept a spouse.
Does the committed intimate relationship start when my partner’s divorce is final? Not necessarily. Under the published rule it can’t start before you began living together, and courts have found a CIR from the move-in date even while a partner’s divorce was pending. But overnight stays while your partner still lived with a spouse don’t count as living together.
Can my partner’s spouse claim the property we bought together? Possibly. Property a married person acquires before separating from their spouse is community property of that marriage, so the spouse may have an interest in it. This is a case-specific question to raise with a lawyer early.
This post is part of our series on committed intimate relationships in Washington. Start with the main guide, What is a committed intimate relationship in Washington, and what happens when it ends?, or read about the Connell factors and how to prove a CIR existed.
Last updated September 2026.
Law Offices of Daniel Ehrlich, Everett. Family law in Snohomish, Island, King, and Skagit Counties. (425) 954-5578.
This article is general information, not legal advice. Every case is different. If you’re separating from a partner you never married and there’s property between you, talk to an attorney.
