The Economist has written a short piece on the theory of privacy as “contextual integrity” developed by my dissertation adviser, Helen Nissenbaum. The article focuses on efforts by John Mitchell, Adam Barth and Anupam Datta, all computer scientists at Stanford University, to turn the philosophical components of contextual integrity into formal expressions that can be incorporated into computer programs:
Contextual integrity, which was developed by Helen Nissenbaum of New York University, relies on four classes of variable. These are the context of a flow of information, the capacities in which the individuals sending and receiving the information are acting, the types of information involved, and what she calls the “principle of transmission”.
It is the fourth of these variables that describes the basis on which information flows. Someone might, for example, receive information under the terms of a commercial exchange, or because he deserves it, or because someone chose to share it with him, or because it came to him as a legal right, or because he promised to keep it secret. These are all examples of transmission principles.
Dr Nissenbaum has been working with Mr Barth to turn these wordy descriptions of the variables of contextual integrity into formal expressions that can be incorporated into computer programs. The tool Mr Barth is employing to effect this transition is linear temporal logic, a system of mathematical logic that can express detailed constraints on the past and the future.
…For example, the Gramm-Leach-Bliley act states that “a financial institution may not disclose personal information, unless such financial institution provides or has provided to the consumer a notice.” This is expressed as:IF send(financial-institution, third-party, personal-information)
THEN PREVIOUSLY send(financial-institution, consumer, notification)
OR EVENTUALLY send(financial-institution, consumer, notification)