Sebastian provides timely and practical advice regarding a broad range of regulatory, public law, professional disciplinary, and commercial matters. He particularly enjoys adopting an outcomes-focused approach to solving legal problems falling across subject matter areas, drawing on his wide-ranging but detailed knowledge of the law to help develop strategic dispute resolution solutions.
Sebastian has particular experience with the law of corporate personality (including the law of insolvency and companies), public-body decision making (including judicial review), professional negligence, real and personal property, trust, health and safety, financial markets, and competition. He also has experience negotiating the interface of tax law with criminal and public law.
He regularly appears as counsel (both led and unled) in court proceedings at all levels, and has been of counsel in a number of professional disciplinary and general civil tribunals.
As well as his work for a wide range of public body and private clients on civil matters, Sebastian conducts health and safety and other regulatory prosecutions. He is also a designated Crown prosecutor, taking a particular interest in financial crime and the interface of criminal and civil law, while prosecuting all types of serious offences.
Sebastian takes an active interest in law reform. He expresses this, and deploys his knowledge of civil procedure, by serving as a member of the Law Society’s Civil Litigation & Tribunals Committee.
Recent and notable work:
Acting, and appearing, for the Financial Markets Authority in relation to its (pending) application for asset preservation orders in respect of the Du Val group, and ancillary matters.
Acting for the Commerce Commission in relation to (pending) appeals and judicial review proceedings in respect of input methodology determination decisions.
Junior counsel for the prosecution in the first successful prosecution of a CEO of a large corporate for breaches of officer’s duties under the Health and Safety at Work Act 2015: Maritime New Zealand v Gison [2024] NZDC 27975; [2025] NZDC 5440.
Contributor to the Law Commission study paper, He Poutama (2023).