The next time a married man or woman glances your way, you might think twice before acting on impulse and frolicking between satin sheets. The scorned spouse could sue you.
Yes, you read that right. You, the paramour, can get hit with a lawsuit that could cost you hundreds of thousands of dollars.
They're known as "alienation of affection" suits, when an "outsider" interferes in a marriage. The suits are allowed in seven states: Hawaii, Illinois, Mississippi, New Mexico, North Carolina, South Dakota and Utah.
The law allowing such legal action dates back to antiquated times when a wife was considered the property of a husband. A broken-hearted hubby could go after his wife's lover -- not with a gun, but with the law.

Раньше по молодости как легла так и дала а теперь сил нет. Одни тенезмы любви.

citizen, have there been any cases?

http://www.illinoislawyerblog.com/2009/06/illinois_car_mogul_sues_for_al_1.html

Узаконенная мстя, так сказать. Особенно для тех, с кого есть что взять. Забрал жену - плати.