William Gummow, a Justice of the High Court of Australia for seventeen years and, in his final years, a non-permanent judge on Hong Kong's top appellate court, died on September 17, 2026. He was 83. "He wrote swiftly and easily, and despite his sudden death, he left behind no reserved judgments," said Justice Mark Leeming, a judicial colleague, in a tribute carried by Lawyers Weekly.

Gummow was born in Sydney in 1942 and educated at Sydney Grammar School before taking an arts and law degree at the University of Sydney. He was admitted as a solicitor in New South Wales in 1966 and spent a decade in practice before being called to the New South Wales Bar in 1976, according to Hong Kong Free Press. Through all of it he kept a foot in the lecture hall, teaching equity and intellectual property at his old faculty at the University of Sydney from 1966 to 1995, work that produced two textbooks still handed to Australian law students long after he left the classroom: four editions of Jacobs' Law of Trusts in Australia and, in 1975, Equity: Doctrines and Remedies. The University of Sydney later awarded him an honorary Doctor of Laws, in 1992.

He was appointed Queen's Counsel and a Justice of the Federal Court of Australia in the same year, 1986, and moved to the High Court of Australia in 1995, where he sat for seventeen years, until 2012. On that court he was part of the bench that decided Wik Peoples v Queensland in 1996, ruling on whether pastoral leases extinguished native title, and Kable v Director of Public Prosecutions for NSW, which set limits on the judicial power the Commonwealth could hand to state courts, per the Law Society Journal. He was appointed a Companion of the Order of Australia in 1997.

Retirement from the High Court in 2012 did not end the working life. Gummow took up professorships at the Australian National University's College of Law and back at the University of Sydney, and in 2013 he joined the Court of Final Appeal of Hong Kong as a non-permanent judge, one of a small pool of overseas jurists the territory's top court has long drawn on. He held that seat for thirteen years, last hearing a case in May 2026 and having committed to sit until July 2028, according to Hong Kong Free Press. Six other international judges had already left that bench since early 2024, leaving him among a shrinking group of overseas jurists still serving on it, and the Hong Kong Bar Association said such judges played an important role in strengthening the administration of justice in Hong Kong, per The Standard.

Announcing his death, the High Court of Australia said he had been "a deeply learned, rigorously analytical and highly collegiate member" of the court who "contributed greatly ... to the content and trajectory of Australian law," according to Queensland Law Society Proctor. Governor-General Sam Mostyn said: "Widely respected for his intellect, scholarship and commitment to the rule of law, Justice Gummow helped shape Australian jurisprudence during his 17 years on the High Court bench."

What stays is the paper trail of a working life that never paused for the ceremony of moving benches: rulings in Wik and Kable still assigned to Australian law students, two textbooks on trusts and equity that outlived his years at the lectern, and a Hong Kong appointment he kept renewing into his eighties rather than treat a Canberra retirement as the end of the job. Few judges cross so completely between the classroom, the bar and three separate courts on two continents, and fewer still are still writing finished decisions, fast and unreserved, at 83.