Is adultery against the law or a felony in Washington state? Could the offenders of such an act spend time in jail?

While many states have them on the books, there has not been a conviction of any such laws since 1983. Plus after the 2003 Supreme Court case of Lawrence v. Texas which dealt with Sodomy but was widened by the court to include the fundalmental right of privacy to sexual relations almost all adultery laws are considered unconstitutional.

A few states still allow adultery to be a civil tort by statue and allows for monetary damages.

So even if the law exists on the books, there would be no court case and no conviction of such.

Also for Washington State it is not even of much interest at divorce under their newer "no fault" divorce laws. It is not relevant in support or even child custody matters.


A search of the laws appears that Washington State no longer has any a active laws on the books,

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A search of the laws appears that Washington State no longer has any a active laws on the books,

I'm sure that you don't mean that all of the RCW has been repealed. But I'm guessing that you looked through the "criminal law" portion and didn't find anything ostensibly criminalizing adultery. :)

I can't find that adultery is illegal, or a felony, in the state of Washington, but if it were, it's not going to get jail time. More serious criminals are clogging up our jails than adulterers. The simple answer is to just file for divorce.