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Privacy & Data

Surveillance for profit and the incredible shrinking expectation of privacy

Digital signage media – video displays on screens ranging from TV-sized monitors in stores to roadside billboards – is maturing into an offline version of behavioral advertising. What effect will this have on consumers' expectation of privacy in public spaces?

Recently, in the UK, a fresh example arose of the growing conflict between these digital signs and privacy laws. Castrol, the maker of motor oil, launched an advertising pilot in which roadside cameras scanned the license plates of passing cars and then digital billboards displayed the license numbers along with the grade of motor oil Castrol recommends for that type of car. The system was able to discern the make and model of each vehicle by running the license number through a database, containing the personal information of tens of millions of drivers, purchased from the British equivalent of the Department of Motor Vehicles.
Castrol's pilot violated a UK ban on the use of driver information for marketing. The government promised an official inquiry. Castrol's expensive interactive advertising experiment was terminated. The fiasco should put digital signage companies and advertisers on alert that they must be aware of privacy laws if they intend to use interactivity and identification technologies.

(To learn more about privacy and digital signage, please see my earlier post, here.)

The Castrol affair also demonstrates that digital signage is adopting surveillance technologies previously used only by law enforcement agencies. Numerous municipal governments have installed networks of cameras to scan license plates and check for outstanding warrants, monitor vehicles associated with past criminal activity, and levy traffic congestion charges. Likewise, both governments and digital signage companies monitor individuals through facial recognition. The difference, however, is that while the government usually conducts such surveillance for security, digital signage does it for profit.

Both government and private sector entities generally operate under the same legal theories when they scan objects such as license plates or human faces. When consumers are in public places, the law says, they have a diminished "expectation of privacy". Thus, while marketers or law enforcement may need consent (or a warrant) to gather information about a consumer at home, almost anything that can be gleaned from a consumer in public is fair game for a wide variety of uses. Courts have often justified this policy by pointing out that anybody can observe you in public, and therefore using electronic devices such as a camera to augment normal human senses is permissible. This framework gives digital signage a lot of power as it is unique among behavioral advertising media in that it both collects data and displays ads in public places.

Speaking for myself, although I'm certainly not alone, I have always found the "expectation of privacy" theory as applied to conduct in public places to be disingenuous. A human being – even a team of human beings – cannot be deployed 24 hours a day to record the demographics or license numbers of all passersby, analyze the data, serve up a targeted advertisement on a screen, and then retain the data for later use. It is simply not realistic to equate the human eye with a sophisticated camera connected to a computer network.

The expectation of privacy standard is troublesome on a more fundamental level as well. The reasonableness of the expectation is shaped by forces over which consumers have little or no control, such as changes in technology and their adoption by zealous law enforcement or intrusive marketers. The ongoing proliferation of surveillance technology for security and advertising means that the public expects to be scrutinized ever more closely, even though studies demonstrate this is not what the public wants. Subsequently, the expectation of privacy always shrinks.

So when will privacy cease being a mere expectation and actually become more like the fundamental legal right it's supposed to be?

There are indications that the legal landscape is changing on the issue of privacy in public. For example, last May the New York Court of Appeals ruled that law enforcement needed a warrant to attach a GPS device to a suspect's car and track its movements on public thoroughfares. The court rejected the traditional analogy of the human eye, stating "GPS is not a mere enhancement of human sensory capacity. The massive invasion of privacy entailed by the prolonged use of the GPS device was inconsistent with even the slightest reasonable expectation of privacy." On the other hand, a Wisconsin Court of Appeals ruled the opposite way on the same issue about a week prior to the New York decision.

Enactment of baseline federal privacy legislation would be preferable to relying on narrow court rulings. There some are encouraging signs here as well. Last April, Rep. Bobby Rush introduced a bill that would require information brokers to adopt privacy and security measures for personal information they hold in electronic form. Digital signage companies who identify individuals likely meet the bill's definition of "information brokers." Representative Rick Boucher has also declared his intention to introduce a bill that would require privacy controls for Internet marketing.

The impetus for these bills arose in part from the controversy surrounding web-based behavioral advertising. As out-of-home targeted marketing becomes common enough to track consumers as they move through public spaces, will there be the same impetus for offline privacy legislation? Or will the public's expectation of privacy continue to shrink until leaving the house means facing an onslaught of unchecked advertising that scrutinizes our bodies and our property and calls to us by name?