Sony may have an even stronger shield against use of the emails in legal proceedings than item-by-item objections. "Fruit of the poisonous tree," that is evidence obtained unlawfully as here, is generally excluded in legal proceedings. The most widely known application of that rule is the exclusion of evidence that law enforcement officials obtained in violation of a criminal suspect's constitutional rights. That same exclusionary rule may apply to consideration of these hacked emails. So, say, stars seeking to break their contracts because of what is said in those emails may be unable to use the emails to invalidate their contracts.
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Sony and the person asserting a claim based on the emails may have a contract that requires any dispute to be resolved through private arbitration. If a particular legal dispute goes to private arbitration instead of being aired in state or federal court, yet a third set of rules may apply. The rules of evidence that apply in an arbitration fall somewhere between the anything goes "rules" that apply in the court of public opinion and the rules of evidence that apply in court which limit what comes in, generally speaking, to the kind of evidence experience has shown is trustworthy. If a particular set of emails is especially relevant to the particular legal claim before the arbitrator, the uncertainty of whether such evidence will be considered may drive both parties to settle.
Maybe at the end of the day these emails will have the most significant impact on individual dealings with the people who wrote them, even in matters that have not yet registered with the broader public and even in matters will never be considered in court. The emails provide unfiltered insight into attitudes, tactics, priorities.
But it is wrong to say that such emails represent the only indication of such things. A snapshot is not a movie any more than a misdirected throw is an entire football game or the sum total of a quarterback's career. There's more to be sure.
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And yet emails that were never intended to be public unavoidably will have consequences, most of which will never be tested in a court of law or arbitration and some of which may never be aired at all, such as the unreturned call or, ironically, the unanswered email. It is the consequences that have no appeal that may cause the most lasting harm. The "e" in email stands for "evidence."
Commentary by Dan Eaton, a partner with the San Diego law firm of Seltzer Caplan McMahon Vitek where his practice focuses on defending and advising employers. He also is a professor at the San Diego State University College of Business Administration where he teaches classes in business ethics and employment law. Follow him on Twitter @DanEatonlaw.