My instinct told me she was being unfaithful, but I couldn't prove anything. I planted a recorder in the lining of the couch. I left it there for a week while I was fishing out at sea-no, literally, on a fishing boat. I mean, it was a very clear recording. According to John Dresden, the private investigator who owns Spy Tech, at least 40 percent of his business is tape recorders, and the use of such items for domestic espionage is increasing.
Federal law prohibits eavesdropping.
The only problem is, it's a single-party consent rule, meaning only one of the people involved in the conversation needs to know it's being taped. But state laws vary. In California, for example, both parties need to be informed. Of course, that doesn't prevent someone from using a recorder surreptitiously. When I played her the tape, she turned pale white.