Dennis is Australia’s foremost authority on the interpretation of legislation and one of the leading authorities on Commonwealth administrative law. His distinguished career as an academic based at the Australian National University was interrupted by a substantial period as Commonwealth Ombudsman.
He has written Australia’s leading textbooks on Statutory Interpretation and Delegated Legislation and is editor of LexisNexis Australian Administrative Law Service. His texts on administrative law and statutory interpretation are widely used and quoted reference works.
Dennis has considerable practical experience in conducting investigations and inquiries for both the Australian Government and for the ACT Government. In February 2013 Dennis was appointed by CSIRO as an independent investigator for allegations of workplace bullying and other unreasonable behaviour. In 2011/2012 Dennis was a co-leader of the Review of Allegations of Sexual and Other Abuse in Defence for report to the Minister for Defence.
Dennis was named Best Lawyers® 2015 Canberra Government "Lawyer of the Year", 2014 and 2018 Canberra Regulatory Practice "Lawyer of the Year", 2013 Canberra Public Law "Lawyer of the Year" and 2011 Canberra Government "Lawyer of the Year". He has also been listed in Best Lawyers® as one of Australia's leading lawyers in the Government Practice, Intellectual Property Law, Public Law and Regulatory Practice categories.
- Co-leader, Review of Allegations of Sexual and Other Abuse in Defence (2011) for report to the Minister of Defence and the Department of Defence;
- Chair, Panel to Review Transparency in Decision-Making in the Therapeutic Goods Administration (2011);
- Advice to the Hong Kong Government on powers of the Legislative Assembly to amend legislation (2011);
- Advice to the Commonwealth Ombudsman on the application of the Freedom of Information Act 1982 (Cth);
- Numerous advices to Australian government agencies on the interpretation of legislation;
- Numerous advices to Australian government agencies on administrative law implications of decisions;
- Advices on scope of jurisdiction for the Commonwealth Ombudsman;
- Advising on Compensation for Detriment caused by Defective Administration (CDDA) claims for the Department of Defence.
- Bachelor of Laws
- Master of Laws
- Doctor of Philosophy
- Barrister and Solicitor: Supreme Courts South Australia, Australian Capital Territory, New South Wales: High Court of Australia
- Law Societies, Australian Capital Territory and New South Wales
- Australian Institute of Administrative Law
- Statutory Interpretation in Australia (1st edition, 1974, 7th edition with RS Geddes, 2011)
- Delegated Legislation (1st edition, 1978, 3rd edition with S Argument, 2005, 4th edition in preparation)
- Australian Administrative Law Service, LexisNexis (Editor since 1979)
- Commonwealth Administrative Law (1986)
- Administrative Appeals Tribunal (1st edition 2003, 2nd edition 2007)
- Advices on scope of jurisdiction for the Commonwealth Ombudsman
- Advising on Compensation for Detriment caused by Defective Administration (CDDA) claims for the Department of Defence