Evan Schuman's StorefrontBacktalk

The purveyors of such technology have also argued that shoppers have no “expectation of privacy” as they shop in the mall and that this technology is “no more intrusive than having shoppers followed as they shop.” After all, there are cameras all over the mall that can track traffic.

First, there is a difference between monitoring traffic and monitoring individuals. Second, yes, this is as intrusive as following individual shoppers around at the mall. And just as creepy. A notice at the mall is not enough to provide “consent,” especially where the only way to opt out of this monitoring is to either not shop or not have a cell phone—neither option is too attractive.

And yes, Google tracks a lot of information when you shop online. But there are ways (anonymizers, for example) to mask some of this information. Plus, two wrongs don’t make a right. In the end, the FootPath technology is of questionable legality and of even more dubious practicality. The market place has spoken, and the malls have responded. That’s why you have a full-fledged privacy review of any new technology before you deploy it!

Do consumers (or anyone else) have any expectations of privacy in their locations or activities while they are shopping in a public place? What technologies are appropriate for collecting and storing information about consumer behavior? Can we use cameras, facial recognition, data mining or other tracking programs? How do we compare expectations of privacy in “public spaces” like shopping malls with the types of behavioral activity routinely collected and used by companies like Google and others online? Is it legal to collect this information? Like everything else in life and law, it depends.

OK. First and foremost, is what the FootPath system was proposing to do in the United States legal? My answer is, probably not. Recognize that laws related to collection and use of electronic information—particularly from telecommunications providers—is murky at best. You have the federal and state wiretap laws, each with different requirements and definitions. You have the “stored communications” act, relating to the collection or interception of stored communications. You have a variety of state laws, such as those in California, Utah, Minnesota, Florida, Oklahoma, Hawaii and Pennsylvania, that prohibit the installation and use of “tracking devices.” You also have the federal “pen register” and “trap and trace” statutes, which prohibit the installation and monitoring of such devices without either a warrant or some legal exception.

To understand whether FootPath is “legal” you first have to understand what the technology does (and what it does not do) and who is using it. The technology appears to just listen to and record the signal strength of any cell phones that come within range. From the signal strength, the device can determine that there is a phone within range, the carrier (because different carriers use different frequencies) and, through the process of “triangulation” (examining signal strength to three different antennas), the location of that phone at any time it is within range of the monitoring system. It does not appear to record the phone number or other identifying information about the phone (the Electronic Serial Number or the International Mobile Equipment Identity [IMEI] number). It does not record the contents of calls, texts, E-mails or anything transmitted over the network. It just measures signal strength of the transmitter inside the phone, and from that it infers location. Clearly, the technology must also have a way to identify a particular phone once it is in range (so it can track that phone throughout the mall). But this does not mean that the technology knows in any meaningful way who owns the phone. Well, at least not yet.

The signal strength is continuously “broadcast” by your cell phone and is not encrypted (nor could it be, because it is not content). The Footpath technology could be “active”—that is, “pinging” all phones within range, or “passive”—that is, just looking for a signal. Either way, it is just measuring ambient radiation broadcast throughout the mall. You don’t have a “reasonable expectation of privacy in the strength of you cell phone’s transmissions.” Or do you?

If you disagree with me, I’ll see you in court, buddy. If you agree with me, however, I would love to hear from you.