I imagine a lot of veiled threats will be made following the hacking of marital-affair site Ashley Madison, whether it be via third parties or via inevitable divorcing parties.
Is it legal for a spouse who learns of his/her spouse's infidelity through this hack to use it in divorce case? Or does it fall under the theory of being fruit from the poisonous tree?
If the spouse obtains the information via legitimate means (off the long list of names that could be revealed on the Internet), it is my belief that it can be admissible evidence during a divorce case.
However, despite common belief, in most states (including New York), courts would not care much about the evidence even if it could be submitted. Judges do not often concern themselves with infidelity. Therefore, even if the spouse finds out about his/her spouse being a member of Ashley Madison and all of the gory details of his/her sexual exploits, it will not typically affect divorce litigation and often may not even become an issue brought to the court's attention.
The only way a judge would be interested in a litigant's love life would be if it affects the children of the marriage or the finances.
So, if a spouse has lied in a legal document about not spending money on extra-marital affairs, and his or her name appears on the Ashley Madison client list, then that person's credibility could be questioned. Often, people will use posts on social media simply to impeach one's credibility in divorce cases. Imagine the story of a parent claiming poverty when being directed to pay child support, but then posting a picture of a brand new car on a Facebook page.
Extra-marital affairs only become relevant when considering any non-marital expenses that are incurred with marital income. So, the $19 fee that the spouse spent on the "Full Delete" service for the Ashley Madison site will be considered marital waste (as would any other monies spent on the site and the monies spent on the hotels, etc.) and that would be a credit back to the marital pot.
This results in spouses scouring through credit-card statements searching for flights, jewelry and lingerie purchases and expensive restaurant bills searching for marital credits (more often than not spending more in legal bills dealing with this issue than the amounts actually spent).
The real expense that the members of Ashley Madison will incur should their membership lead to a divorce has to do with the guilt and embarrassment of being caught.
Should the Ashley Madison hackers reveal the names and personal details of its clients, it will be a busy summer for therapists, head-hunters and most of all, divorce attorneys.