Mrs. Obrien suspected her husband was cheating, so she installed Spector, a spyware program that monitors activity on your own computer. She is alleged to have caught Mr. Obrien in intimate conversations with women using on-line chat rooms. However, the Court ruled that the evidence she gathered was an electronic communications protected by the anti-wiretab statute as explained here in an ABA story. The article seems to suggest that employers could not use information gathered via monitoring of a companies’ employees. I think the difference is that the employees have consented in advance to the monitoring as a condition of employment and the equipment is typically fully owned by the employer. I don’t think the O’brien v O’brien case means nearly as much as is suggested.