"...New York defines an adulterer as a person who 'engages in sexual intercourse with another person at a time when he has a living spouse, or the other person has a living spouse.'"
Legally speaking, gender has nothing to do with being an adulterer, really. A woman can be an adulterer if she cheats on her spouse with another woman. A man can be an adulterer if he cheats on his spouse with another man.
So, is a threesome adultery? It might be, depending on the specific laws in the state it occurred in, but it would depend on the state of each partner and the marriage after the sexual behavior occurred.
If it ends up interferring with a marriage then it would, most likely, be considered adultery on both halves of the marriage. Threesomes are, typically, willfully so if it "maliciously" hurt the marriage in the end then both partners would have committed adultery even though it was with the same person at the same time.
I'm sure there have been cases where two people committed adultery with the same person, whether they knew it at the time or not, and both were considered adulterers. The only difference with the threesome is that all three people are in the same place at the same time. It all depends on what happens to the marriage from there on out, apparently. [ Peeps's advice column | Ask Peeps A Question ]
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