Legal Question in Family Law in Washington

Re: Married and taking a mistress.

The basis for marriage (of a non-same sex couple) in WA is that the parties want to stay married. The party who has multiple spouses is engaged in a crime (bigamy), having a mistress is not a basis for divorce, but the mistress has an inferior position in all respects to spouse. You can't have a husband in common (yet). If one person is married to the man, that person will have rights superior to any other person in their estate and in other ways. The only way that I could see to work this situation out would be for all of you to have a private cohabitation agreement. Some of the considerations in the agreement would be: details of the sharing of living expenses during the course of the relationship; division of joint property upon termination of the relationship; and the retention of separate property acquired prior to, and after, the execution of the agreement. Your situation would more complicated to address than a couple's agreement, because you would have to be prepared to handle the exit of one party, leaving two parties in the agreement (or would you want it to result in the complete dissolution of the agreement?). Your agreement will have much in common with a partnership agreement and may well look less like a traditional cohabitation agreement. You may also want to address how other people could enter the agreement.