The key is to ask lots of questions before buying and using such devices, such as whether the tracking information is stored, where it is stored, who can access and view it, and whether any third parties ever have access to the information, Tien said.
The legal questions
Behnam Dayanim, an attorney with Los Angeles-based Paul, Hastings, Janofsky & Walker LLP, said the legal lines on the use of such devices can be blurry.
"The acceptability or permissibility of these techniques depends on several factors, including where they were activated, who is undertaking the activity and what notice is provided to the subject of the activation," Dayanim said. "There are different degrees of privacy interests. The greatest privacy interest is in your own home."
In other words, homeowners could claim they are permitted to collect information about others who are inside their homes. But if someone collects information about you in your home without your permission, that would be an invasion of your privacy, he said.
A sampling of security gear
There's an ocean of high-tech personal security devices out there. These are only a few:
- SecureShot Bird Feeder DVR (Productive Electronics LLC, $699)
- SecureShot Teddy Bear Camera (Productive Electronics LLC, $699)
- Trackstick Mini (Telespial Systems Inc., $289)
- Zoombak Universal A-GPS Locator (Zoombak LLC, $100)
Audio recorders (with automatic voice activation)
- Olympus VN-6200PC (Olympus America Inc., $60)
- Sony Digital Voice Recorder ICD-SX700D (Sony Electronics Inc., $200)
"You [should] talk to somebody about the law" when they are making a purchase, SpyGear4U's Scott said. "By law people aren't allowed to record a phone conversation if the other person isn't aware of it. We have the laws posted on our site, but we can't be the police."
He admitted that there are a lot of illegal products available on the Internet. "I don't carry them," Scott said, including devices sold in Europe and elsewhere that allow someone to capture others' cell phone calls on their own phones in real time so they can listen in. "It's not something I want to sell," Scott said. "I don't want a knock on my door six months from now" from the police.
"I think your legal position is much stronger [if you use this type of equipment] in your own home," Dayanim said. "I don't think the law is completely settled on nanny cams . . . but I think there are certainly strong consensuses to a claim."