In short, the court ruled that the rap sheet information was not simply public because it had once been public, but that a reasonable expectation of privacy existed because of the “practical obscurity” of the documents. The court ruled that, despite the rap sheet information having been public at one point, the cost to identify, locate and access that information created a reasonable expectation of privacy on the part of the brothers. The decision affected a number of different aspects of how agencies attempt to balance privacy and access when considering FOIA requests, but the most germane to the present conversation is the introduction of the concept of obscurity. The case progressed through the district courts and was finally accepted by the Supreme Court in order to resolve the issue of whether releasing the documents was an unwarranted invasion of privacy despite the requested information having at one point been a matter of public record. The FBI refused to release the rap sheets and the journalists sued, limiting the request to publicly available information. At that time, journalists requested under the Freedom of Information Act the rap sheets of four brothers who had allegedly obtained defense contracts from an improper arrangement with a corrupt congressman. The term practical obscurity first occurs as a matter of jurisprudence in the 1989 Supreme Court decision cited above. Extending the definition of obscurity beyond the Supreme Court decision gives us a chance to see how time-bound “forgettable” information plays a vital role in communication and how a market is developing in modern technical communication circles to reclaim the element of obscurity that was once a constant but unseen aspect of our every day behavior and interactions. Images and text messages literally self-destruct and can no longer be viewed by the receiver.

However, unlike iChat and other vendor-specific, real-time data sharing and communication tools, the new genre of messaging applications allows the sender to set an expiration date on the data being shared.

In many ways the base communicative activities that these applications enable are no different from the standard activities mobile technologies have been providing for well over a decade. Snapchat, Wickr and iDelete are all mobile communication applications that have emerged in the last several years for sharing images, videos and text messages among social networks of friends and colleagues. The emergence of a new trend in social networking and communication – self-destructing data – sets the stage for obscurity to return to the information marketplace in force and signals a growing awareness of the public eye in modern social networking communication. By refining the traditional public/private dichotomy through an understanding of individuals' desire for this kind of obscurity, information policy advocates can better understand the complex set of factors that inform the expectations of their constituents. Obscurity in this somewhat technical sense gives us an interesting theoretical framework for understanding the frontier between private and public information in an era when aggregation has become a dominating force in the information marketplace.

While no single piece of information under the FOIA request was private, the aggregate collection of such obscure information was considered so costly as to imply a certain level of privacy. The court ruled that because the cost associated with obtaining certain information was so high there was a reasonable expectation of privacy on the part of the subject of that information and that the Department of Justice could not be compelled under the federal Freedom of Information Act to divulge information that it had compiled from otherwise publicly available records. This decision created a legal precedent for the idea that some information, despite being made public in a specific place or at a specific time, is for all practical purposes private (or “obscure”). Practical obscurity is a legal term introduced in 1989 by the Supreme Court in the U.S.

Trusting obscurity