Under the pseudonym “Hugo Cornwall”
- The Hacker’s Handbook, Random-Century, 1985, 1986, 1988, 1989.
- DataTheft, Heinemann Professional, 1987, Mandarin Paperbacks, 1990.
- The Industrial Espionage Handbook, Century 1991, Ebury Press, 1992.
Under own name
- The PC Security Guide 1993-1994, Elsevier, 1993.
- Why Legislation is the not the answer; the limits of the Law. Compacs 91, 15th International Conference on Computer Audit, Control and Security, IAA
- Computer Forensics: an Introduction. Compsec ’92, Elsevier.
- Computer-Aided Industrial Espionage. Compsec ’93, Elsevier.
- Industrial Espionage: Analysing the Risk. Compsec ’94, Elsevier.
- Various practitioner-orientated articles appear passim in Computer Fraud and Security Bulletin, published by Elsevier and Virus News International and Secure Computing, published by West Coast Publishing.
- The computer security sections of Handbook of Security and Purchasing and Supply Guide to Guide to IT both published by Croner.
- Imaged documents code. Computer Fraud & Security, Apr 1996.
- England ponders trade secrets law. Computer Fraud & Security, Jan 1998.
- Investigating Computer Crime (book review). Computer Fraud & Security, Sep 1997.
- Fraud Watch: A Guide for Business – Ian Huntington and David Davies (book review). Computer Fraud & Security, Apr 1995.
- Information Warfare: Chaos on the Electronic Superhighway – Author: Winn Schwartau (book review). Computer Fraud & Security, Jun 1995.
- Computer-Related Risks – Author: Peter G Neumann (book review). Computer Fraud & Security, Jul 1995.
- Downloads, Logs and Captures: Evidence from Cyberspace. Journal of Financial Crime, October, 1997, 5JFC2 138-152.
- Intrusion Detection Systems as Evidence. RAID 98 Conference, Louvain-la-Neuve, Belgium; also in Intrusion detection systems as evidence, Computer Networks, Volume 31, Issues 23-24, 14 December 1999, Pages 2477-2487.
- Legal Reliability in Large Scale Distributed Systems. IEEE Symposium on Reliable Information Systems, COAST/Purdue University, 1998.
- Digital Footprints: Assessing Computer Evidence. Criminal Law Review (Special Edition, December 1998, pp 61-78).
- Co-author: CyberCrime: Risk and Response. International Chamber of Commerce ICC Publication 621, 1999.
- Sommer, P: Evidence in Internet Paedophilia Cases. Computer and Telecommunications Law Review, Vol 8 Issue 7; [2002] CTLR, pp 176-184.
- Sommer, P: Evidence in Internet Paedophilia Cases; a case for the Defence in “Policing Paedophiles on the Internet” ed McVean & Spindler, New Police Bookshop for the John Grieve Centre, 2003.
- Computer Forensics Education, Yasinac, Erbacher, Marks, Pollitt, Sommer. IEEE Security & Privacy Vol 1 No 4 p 15, July 2003.
- The future for the Policing of Cybercrime. Computer Fraud & Security Bulletin, January 2004, pp 8-12.
- Cybercrime (co-author) and Computer Aids chapters in Fraud: Law, Procedure and Practice, Lexis-Nexis / Butterworths, 2004, 2009, 2013.
- The challenges of large computer evidence cases. Digital Investigation Vol 1 Issue 1 2004 16-17.
- Digital Evidence: a Guide for Directors and Corporate Advisors, Information Assurance Advisory Council, September 2005, revised editions November 2008, November 2013.
- Two Computer Misuse Prosecutions. Computers and Law Vol 16 issue 5, 2006.
- Criminalising Hacking Tools. Digital Investigation Vol 3 Issue 3 2006 68-72.
- Meetings Between Experts: a route to simpler fairer trials. Digital Investigation diin.2008.11.002.
- Forensic science standards in fast-changing environments. Science and Justice 50:11, 12-17, March 2010.
- Reducing Systemic Cyber Security Risk, OECD, Paris, January 2011.
- Police Powers to Hack. CTLR, 2012.
- Submission to Joint Committee of the Draft Communications Bill August 2012.
- Response to Home Office Consultation on new statutory powers for forensic science regulator December 2013 .
- Digital Surveillance, Open Rights Group, May 2013, 2 sections.
- Two Guardian Comment is Free pieces on GCHQ oversight.
- Stronger Oversight of GCHQ – How?
- Big Data and privacy: DI commentary. Digital Investigation, 2015 pp 101-103.
- Accrediting digital forensics: what are the choices? Digital Investigation, Vol 25, June 2018 116-120.
- Digital Evidence Handbook. Amazon / Amazon Kindle, April 2017.
- Reforming the Computer Misuse Act 1990 (co-author). CLRNN 2020.
- Sitting on the steel fence: my dialogue with the intelligence world. about:intel 2020.
- Response to Independent Review of the Investigatory Powers Act 2016 (Anderson), March 2023 .
- Evidence from hacking: a few tiresome problems. FSI:DI 2022.