On the legality of polyamory.

If you didn’t already know, polyamory is the practice of having multiple romantic relationships at the same time with the full knowledge and consent of everyone involved. These relationships usually include sex.

My wife currently sees two men besides me, I also date two other women. I understand this may be morally objectionable to some people, but I never considered the possibility that we were criminals until I read this post by pkbites in the thread on blue laws.

So, a few questions:
Are my wife and I currently breaking the law in Illinois?
In what states besides Wisconsin, if any, would we be breaking the law if we took our dates there?
Are there any other western, developed countries (as opposed to say, Saudi Arabia) that we should be careful about planning a visit to?

Finally, to what degree are these laws actually enforced? I recall from my Army days that adultery was forbidden by the UCMJ, but the JAGs told us it was hardly ever charged by itself – usually it was just tacked onto a rape charge if the perpetrator was married.

Well in Australia apparently we got rid of Adultery laws in the early 1970’s:

So unless theres another relevant law looks like Polyamory is legal down under.

From what I can find Googling, the most recent successful prosecution on an adultery charge in the US was In Virginia in 2003. So, given how common this ‘crime’ is, I’m thinking it’s not taken very seriously.

OTOH, the Michigan Supreme Court issued an advisory in one of its opinions that the letter of the statues in that state could result in life sentences for adultery when committed in association with other felonies.

Here (warning, PDF file) is a copy of the relevant Wisconsin statute–see section 944.16. I couldn’t find a master list of state adultery laws; but it looks like the statue in Illinois, if it’s even still on the books, had adultery as a misdemeanor. So your wife is risking a fine, if anything at all.

Ah, the Wikipedia article on Polyamory also points out that Bigamy laws in some states may be broad enough to technically prosecute if someone is cohabiting with multiple partners.
“At present, the extension to multiple-partner relationships of laws that use a criterion similar to that adopted in the UK, i.e. “married or living together as married” remains largely untested. That is, it is not known whether these laws could treat some trios or larger groups as common-law marriages.”

It’s very likely that Lawrence v.Texas would invalidate many of these statutes, but until they are either repealed or tested, that remains conjecture.

Has there ever been a “divorce” case involving one member of a multiple poly relationship (who wasn’t legally married) wanting out and trying to obtain assets or get child visitation rights? If not I’m guessing its only a matter of a time…