Roger Clarke's Web-Site

© Xamax Consultancy Pty Ltd,  1995-2024
Photo of Roger Clarke

Roger Clarke's 'The Digital Persona and Law'

The Nature of the Digital Persona
and Its Implications for Data Protection Law

Notes of 5 January 2014

For presentation at Bahçesehir Üniversitesi, Besiktas on 20 January 2014

Roger Clarke **

© Xamax Consultancy Pty Ltd, 2013-14

Available under an AEShareNet Free
for Education licence or a Creative Commons 'Some
Rights Reserved' licence.

This document is at

The supporting slide-set is at


An understanding of the the Digital Persona concept, and its relationship to individuals and their identities, is central to the field of identity management and authentication. Yet, despite its importance, it is very poorly understood by information systems practitioners and even by researchers in the field. This seminar explains the concept within the context of a comprehensive theory of identity, and considers the concept's implications for the collection, storage, use and disclosure of personal data, and in particular the authentication of assertions of fact and of identity.

Primary References

The paper that introduced the concept is here:

Clarke R. (1994) 'The Digital Persona and its Application to Data Surveillance' The Information Society 10,2 (June 1994) 77-92, PrePrint at

Its place in a comprehensive model of identity is explained here:

Clarke R. (2009) 'A Sufficiently Rich Model of (Id)entity, Authentication and Authorisation' Proc. IDIS 2009 - The 2nd Multidisciplinary Workshop on Identity in the Information Society, LSE, London, 5 June 2009, Revised Version at

A paper is in press on the history of the digital persona:

Clarke R. (2014) 'Persona Missing, Feared Drowned: The Digital Persona Concept, Two Decades Later' Information Technology & People 27, 3 (September 2014), PrePrint at

Other References

Clarke R. (1994) 'Human Identification in Information Systems: Management Challenges and Public Policy Issues' Info. Technology & People 7,4 (December 1994), at

Clarke R. (1999) 'Anonymous, Pseudonymous and Identified Transactions: The Spectrum of Choice', Proc. IFIP User Identification & Privacy Protection Conference, Stockholm, June 1999, at

Clarke R. (2001a) 'The Fundamental Inadequacies of Conventional Public Key Infrastructure' Proc. Conf. ECIS'2001, Bled, Slovenia, 27-29 June 2001, at,

Clarke R. (2001b) 'Authentication: A Sufficiently Rich Model to Enable e-Business' Review Draft of 26 December 2001, at

Clarke R. (2003) 'eAuthentication Realities You want to authenticate what???' Xamax Consultancy Pty Ltd, August 2003, at

Clarke R. (2004) 'Identity Management: The Technologies, Their Business Value, Their Problems, Their Prospects' Xamax Consultancy Pty Ltd, March 2004, at

Clarke R. (2008) '(Id)Entities (Mis)Management: The Mythologies underlying the Business Failures' Invited Keynote for Identity Management in New Zealand, Wellington, April 2008, at

Clarke R. (2009-10) 'A Sufficiently Rich Model of (Id)entity, Authentication and Authorisation' Proc. IDIS 2009 - The 2nd Multidisciplinary Workshop on Identity in the Information Society, LSE, 5 June 2009, at, and 'Glossary', at, current version at

Author Affiliations

Roger Clarke is Principal of Xamax Consultancy Pty Ltd, Canberra. He is also a Visiting Professor in Cyberspace Law & Policy at the University of N.S.W., and a Visiting Professor in the Research School of Computer Science at the Australian National University. He is also Chair of the Australian Privacy Foundation (APF), 2006-14, and has been Secretary of the Internet Society of Australia (ISOC-AU) since 2012.

xamaxsmall.gif missing
The content and infrastructure for these community service pages are provided by Roger Clarke through his consultancy company, Xamax.

From the site's beginnings in August 1994 until February 2009, the infrastructure was provided by the Australian National University. During that time, the site accumulated close to 30 million hits. It passed 65 million in early 2021.

Sponsored by the Gallery, Bunhybee Grasslands, the extended Clarke Family, Knights of the Spatchcock and their drummer
Xamax Consultancy Pty Ltd
ACN: 002 360 456
78 Sidaway St, Chapman ACT 2611 AUSTRALIA
Tel: +61 2 6288 6916

Created: 27 December 2013 - Last Amended: 5 January 2014 by Roger Clarke - Site Last Verified: 15 February 2009
This document is at
Mail to Webmaster   -    © Xamax Consultancy Pty Ltd, 1995-2022   -    Privacy Policy