GIS and Privacy

March 25, 2005

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Ed.Note: Atanas Entchev joins Directions Magazine as a columnist.

Are GIS systems privacy intruders, or do they merely expose unrealistic privacy expectations? I think it is more of the latter.Just like a GIS exposes slivers and overlaps in property maps, but does not create them (as many tend to think), it sometimes exposes privacy issues where they existed previously.And just like the value of a stock goes up or down because of how well a company performs relative to the stock analysts' expectations, the "privacy quotient" of a GIS is often measured against the users' perceptions of privacy.

Privacy - Real or Perceived?
Last June a U.S.monthly magazine delivered a unique copy to its 40,000 subscribers.Each copy had a different cover.On each cover was an aerial photo of the subscriber's neighborhood, with a circle around the subscriber's house.The magazine wanted to make a point, and it did.A lot of people were stunned, although the ones I spoke with couldn't explain why.They just didn't think it would be that easy to get an aerial photo of their house.

Last month Google released a Beta version of its interactive online mapping system.It is more than slick and appealing.Google Maps links the map you generate with Google's vast index of Internet searches.The results can be unexpected.When I searched for my name, Google maps came up with the location of my previous place of employment, where I worked more than two years ago.

To a lot of people these would be examples of how GIS is a privacy intruder.To me, these are examples of the public's unrealistic expectations of privacy.Was I surprised that a Google search turned up the name of my ex-employer? I wasn't.But Google made a connection that I no longer make.And when Google put that dot on the map, the information took on a different meaning.

Is GIS the Bad Guy?
When designing and implementing a GIS, we are required to take into account a whole host of non-technical concerns, weighted based on national or local legislation, community customs, business practices, etc.Increasingly, privacy is among the top issues concerning GIS implementers.But the concern seems to be more about perceived privacy.

An example: A typical municipal GIS implementation includes a link to property assessment data.A typical dilemma a municipal official has is: "Should we make this available to the public?" It just feels like there is too much information available at the fingertips.But it is all public information anyway, isn't it? In my many years of experience with municipal GISs, the most common instance of municipal GIS "abuse" is looking up how much one's neighbor paid in taxes - clearly a non-evil, non-malicious query, one that can be easily accomplished in a trip to the tax assessor's office.Nevertheless, "privacy concerns," often left to the discretion of the local official, all too often dictate what will go into the GIS and what to be left out.

Seminars dealing with privacy issues in GIS include examples of how a clever burglar can use the New Jersey Open Public Review Act (OPRA) to gain access to information, and then use GIS to analyze that information, in order to determine where to strike next.A typical example is that of the person requesting information about houses with dog licenses, then about houses where senior citizens live, and then about houses with alarm systems.At which point the municipal official becomes suspicious, denies the information request, and prevents the perpetrator-to-be from firing up his GIS application, executing a Boolean logic SQL query, and plotting out a map of his targets.An unlikely scenario, in my opinion.

Feel-Good Privacy
I am not taking an anti-privacy stance.I am convinced that everyone can benefit from a common, better understanding of the real issues of privacy in GIS, and from having common, realistic privacy expectations. Let us not cripple the GIS system to meet some vague privacy perceptions.Let's deal with real privacy issues, and work to correct privacy misconceptions where they exist.GIS is not the bad guy.Stop shooting the messenger.

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