Justice Preston is the Chief Judge of the Land and Environment Court of New South Wales. 

Prior to being appointed in November 2005, he was a senior counsel practising primarily in New South Wales in environmental, planning, administrative and property law. He has lectured in post-graduate environmental law for over 30 years. He is the author of Australia’s first book on environmental litigation and 155 articles, book chapters and reviews on environmental law, administrative and criminal law.

He holds numerous editorial positions in environmental law publications and has been involved in a number of international environmental consultancies and capacity-building programs, including for judiciaries throughout Asia, Africa and the European Union.

Justice Preston is an Official Member of the Judicial Commission of NSW, Fellow of the Australian Academy of Law, Fellow of the Royal Society of NSW and Honorary Fellow of the Environment Institute of Australia and New Zealand. He was awarded a Doctor of Letters (honoris causa) by Macquarie University in 2018 and a Doctor of Laws (honoris causa) by Western Sydney University in 2022. He is a member of various international environmental law committees and advisory boards, including serving on the Governing Council and as Vice President for Oceania of the Global Judicial Institute on the Environment and Chair of the Environmental Law Committee of the Law Association for Asia and the Pacific (LAWASIA).

Justice Preston is currently a Visiting Professor at Durham University (UK), an Adjunct Professor at three Australian universities, the University of Sydney, Western Sydney University and Southern Cross University, and a former Visiting Fellow at Corpus Christi College and Magdalen College at Oxford University (UK).