is an interesting case, because the information that was obtained was accessible through the Web to anyone, but would have been difficult to find without the services offered by Google. Whereas in this case privacy could perhaps have been maintained because of the difficulty of simply finding the available information, the Google service made it easy to find the information, and made it available for free.

A second privacy concern arises regarding the information that search engine companies collect and store about specific searches performed by users. To service a user’s search request, the specific search terms need not be kept for longer than it takes to return the results of that search. But search engine companies keep that information anyway for a variety of purposes, including marketing and enhancement of search services provided to users.

The potential for privacy-invasive uses of such information was brought into full public view in a request in early 2006 by the Department of Justice (DOJ) for search data from four search engines, including search terms queried and Web site addresses, or URLs, stored in each search engine’s index but excluding any user identifying information that could link a search string back to an individual. The intended DOJ use of the data was not to investigate a particular crime but to study the prevalence of pornographic material on the Web and to evaluate the effectiveness of software filters to block those materials in a case testing the constitutionality of the Child Online Protection Act (COPA).12

The four search engines were those associated with America Online, Microsoft, Yahoo!, and Google. The first three of these companies each agreed to provide at least some of the requested search data. Google resisted the original subpoena demanding this information; subsequently, the information sought was narrowed significantly in volume and character, and Google was ultimately ordered by a U.S. District Court to provide a much more restricted set of data.13 Although the data requested did not include personally identifiable information of users, this case has raised a number of privacy concerns about possible disclosures in the future of the increasing volumes of user-generated search information.

Google objected to the original request for a variety of reasons. Google asserted a general interest in protecting its users’ privacy and


Attorney for Alberto R. Gonzales, McElvain Declaration in Gonzales v. Google, Inc. (subpoena request), available at


Antone Gonsalves, “Judge Hands Google Mixed Ruling on Search Privacy,” Internet Week, March 17, 2006, available at The findings based on the search data were to serve as part of the government’s case in defending the constitutionality of the Child Online Protection Act, a law aimed at protecting minors from adult material online.

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