Privacy in the Open: Transparency and Accountabilty as a Privacy Protection Strategy

Daniel J. Weitzner
Decentralized Information Group
MIT Computer Science and Artificial Intelligence Laboratory

These slides:


Why transparent, accountable systems?

Law and Society -- a pop quiz

  1. How many believe you are subject to law (any law)?
  2. How many of you follow (most) laws? [exclude speed limits]
  3. How many of you read all the laws to which you believe you are subject?
  4. How many have been to a court of law?

General goal: Making the Web 'Policy Aware'

How will the Web finally catch up with the 'real world'?: in everyday life, the vast major of 'policy' problems get worked out without recourse to legal system.

Design goal: instrument the Web to provide seamless social interactions which allow us to avoid legal system the way we do in the rest of life

Punch line: In the shift from centralized to decentralized information systems we see a general trend:

ex ante policy enforcement barriers -> policy description with late binding of rules for accountability

A. Privacy Challenges -- then and now

AT&T TSD 3600 gmail

A. Privacy Challenge -- increased information collection, storage and analysis

B. Privacy Challenge -- inadequate laws

C. Privacy Challenge -- dilemma of consent

Can consent model (EU opt-in or US opt-out) be effective going forward?

Key will be purpose limitation, but we have a dilemma...

Dilemma: limited individual and regulatory capacity to control escalating data uses.

Result of consent dilemma + increased inference power: strict about what's collected but loose about usage

Collection Limitation -> Use Limitation

We're at the wrong end of the privacy spectrum and seeking the wrong results:

privacy today

Collection Limitation -> Use Limitation

Still suboptimal control point:

privacy goal for some

Collection Limitation -> Use Limitation

This is where we should be:

privacy goal for some

Collection Limitation -> Use Limitation


  1. Rules express core values!!
  2. Better allocation of individual and regulatory effort
  3. Often the only logical evaluation point

Collection Limitation -> Use Limitation


Systems: (see Abelson, Hanson, Delgado Kloos, McGuinness talks)


Other users of accountable systems

  1. Health Privacy
  2. Credit Reporting
  3. Copyright management (DRM alternative)


Universal Studios Flickr

Departure from Hollywood content (centralied production) -> Blogs, Flickr and Livejournal (decentralized content we all make)


Google Creative Commons Yahoo Creative Commons search

Move from up-front enforcement barriers (DRM) -> open description of licensing terms (CC) with after-the-fact enforcement as needed

Links and Acknowledgements

For more information see:

Work described here is supported by the US National Science Foundation Cybertrust Program (05-518) and ITR Program (04-012).

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