What law protects the right to anonymity for someone fucking around behind the back of his or her spouse? I don't remember that one. ...
You aren't being creative enough. There are always arguments to be made. I'm sure an aggrieved "cheater" plaintiff could craft many causes of action against the attackers (with varying levels of merit). The first issue in the case would be to determine the applicable law. The jurisdictional contest would probably include (1) Ontario (where the "Ashley Madison" company is apparently based), (2) the state of residence of the victim, (3) the state of residence of the attackers, and (4) any states from which the attack may have been carried out.
Note that
choice of law is completely separate from
forum (i.e. where the case should be filed). A court in one jurisdiction will apply the law of another jurisdiction if the applicable choice of law rules direct it to do so. See, e.g.,
San Diego Gas v. Canadian Hunter Marketing,
132 F3d 1303 (9th Cir 1997) (applying Alberta law to contract dispute in US federal appeals court and noting that "[
i]f the Alberta legislature has concluded that a breakdown in the valuation process renders a contract voidable, it is beyond the province of the courts to impose a new rule").
In the case of hypothetical claims against the alleged attackers of Ashley Madison, it is impossible to say in advance what law will apply. We don't even know what jurisdictions will be involved in the contest. If, however, we assume for the sake of discussion that the law of Ontario will apply, the most plausible claim against the attackers will probably be "intrusion upon seclusion". In
Jones v. Tsige,
2012 ONCA 32, the Court of Appeal for Ontario found that an action lies against a person who "intentionally intrudes, physically or otherwise, upon the seclusion of another or his private affairs or concerns ... if the invasion would be highly offensive to a reasonable person" (at para 70, adopting the formulation of the Restatement (Second) of Torts (2010))). No proof of pecuniary damages is required to prevail on this cause of action, although in the absence of pecuniary harm, the damages awarded will be "measured by a modest ... sum" (para 71).
The key question would probably be whether the illegal obtainment of information that somebody has "cheated" on their spouse is something that is "highly offensive to a reasonable person". At para 72, the
Jones Court says that "intrusions into matters such as ... sexual practises and orientation ... can be described as highly offensive", but the Court wasn't dealing specifically with "cheating". However, it's not really a stretch to argue that illegal obtainment of that information might be "highly offensive" when "viewed objectively on the reasonable person standard" (para 72).
This post does not discuss any causes of action that the plaintiffs might have against Ashley Madison itself. I'll leave those as an exercise.
