The ECPA also prohibits the use or recitation of information obtained from any interception. Most of the cases developed under the ECPA involve wiretapping of telephone and E-mail communications by law enforcement. Civilly, most of the case law, until recently, involved telephone monitoring. Under the ECPA, though, the owner of the communication equipment and services can usually monitor activities from that equipment. And in the marital setting, the courts have generally refused to review unauthorized access of the spouses' electronic communications. (This unwillingness to review possible violations probably wouldn't apply to people merely living together or involved in a relationship and not living together.)
In certain states where they exist, the person being spied upon may be able to seek relief under the common-law tort of invasion of privacy. Although many state courts have held that no such tort exists, the tort generally requires an intentional intrusion, "physical or otherwise, upon the solitude or seclusion of another upon his private affairs, or concerns ... if the intrusion would be highly offensive to a reasonable person."
One of the key conditions to prosecuting an action for invasion of privacy is whether or not the person has a reasonable expectation of privacy.
The courts across the country are finding with more and more frequency that no reasonable expectation of privacy exists with E-mail in the workplace setting. And a court in New Jersey reviewed whether a spouse's accessing of E-mails of the other spouse on a home computer violated New Jersey wiretap laws (modeled closely on the ECPA), finding that no expectation of privacy exists on a home computer when the family is involved and that the seized E-mails could be introduced as evidence of infidelity. This case focused largely on whether the spouse violated the section of the ECPA and the state equivalent by accessing "stored communications." The state judge ruled that E-mails, once saved on the hard drive automatically in the sent E-mail folder, were no longer stored communications under the act and were legally accessed, copied, and admitted into court.