Undoubtedly the surveillance industry has grown over the past 20 years.  Electronic manufacturers now make spy technology that is more durable, effective, and affordable than anything that had come onto the scene since the nineties. 

As this technology becomes more affordable and prevalent, one must ask what are the limits of the law with this technology?  When can you use it and when can you not?

According to national nanny cam laws, it is generally considered legal to videotape nannies without their permission.  However, if you videotape using audio, then the act is dangerously close to being considered as eavesdropping or wiretapping.  The laws that explain the nature of eavesdropping or wiretapping vary from state to state.

One should never expect privacy in the home of another, and many parents in San Francisco CA and advocates of the nanny cam argue that installing hidden cameras and spy technologies in their home is not an invasion of privacy.

US courts, in fact, found that evidence obtained via a nanny cam/hidden camera was legitimate in the case of the State v. Diaz, 706a.2d 264 (1998), generally considered the most prominent case on this topic.  The prosecution was for assault and child endangerment.  The court ended up concluding that it was ones constitutional right to film in their own home, and the nanny was not  protected under any sort of privacy laws in this case.   However, a recording with sound (and without the permission of the nanny) is illegal in many states, including: California, Connecticut, Delaware, Florida, Hawaii, Illinois, Louisiana, Maryland, Massachusetts, Montana, Nevada, New Hampshire, Oregon, Pennsylvania and Washington state.  Then again sound on a video can be muted, and it is likely that a video with muted sound could be admitted as evidence. 

And yet nanny cams might not be as private as you think.  In fact, many who install this novel security in their homes in San Francisco CA, end up opening a window on their activities to the outside world without even knowing it.   Since most nanny cams are wireless cameras (transmitting the signal from the camera to a base, usually a television or computer), signals can be easily intercepted.  A camera with a signal-scrambling function may be able to block such interception, though otherwise your images can be intercepted from up to a quarter-mile away.  But if a court finds that the video was used for any purpose other than protection of a child or guarding against theft for instance, for the purpose of voyeurism or commercial purposes then the video can likely be used against you, the owner of the nanny cam.

Wiretapping laws only protect against audio wiretapping and therefore almost anyone can spy on your nanny cam without legal punishment. It has been demonstrated that a simple drive around the suburbs with a security expert could easily pick up the signals of nanny cams and view the images being filmed inside of private homes.  Basically anyone with a little computer knowledge can hack into your live-feeds and see whats going on in your home.

Some who have been cautious of this fact, have decided to create no camera zones, or carefully place cameras in areas where privacy wasn't a concern.  In general, though, the prevalence of nanny cams has soared and their benefits may outweigh their disadvantages.