Rear Admiral Peter Ross Sinclair, AC (born 16 November 1934) is a retired senior officer of the Royal Australian Navy who served as the 35th Governor of New South Wales from 8 August 1990 to 1 March 1996. Born in Manly, New South Wales, he was educated North Sydney Boys High School before joining the navy through the Royal Australian Naval College.

Over a 41-year career, Sinclair saw active service in Korea, Malaysia, Vietnam and in relief operations following Cyclone Tracy, and commanded the naval base HMAS Penguin. He later rose to high command, serving as Director of Naval Plans and as chief project officer during the establishment of the tri-service Australian Defence Force Academy, and then serving as its first commandant. In 1987 he was appointed Flag Officer Commanding HM Australian Fleet, which was redesignated as Maritime Commander Australia the following year. In 1989 he was appointed as Deputy Chief of the Naval Staff but served only briefly until his retirement later that year.

When his friend and navy colleague, Sir David Martin, resigned his commission as Governor of New South Wales in August 1990 due to an advancing medical condition, Sinclair was appointed to succeed him. He retired in 1996 while controversy of Carr's proposed changes of the Governor's role emerged in regard to his successor.

Peter Sinclair was born in Manly, New South Wales on 16 November 1934 to Gordon and Dorothy Sinclair. After being educated at North Sydney Boys High School, Sinclair joined the Royal Australian Navy and entered the Royal Australian Naval College as a Cadet in January 1948. After several years he was sent for further studies at the Royal College of Defence Studies in London. Sinclair served on various ships including HMS Vengeance, HMAS Australia, HMAS Arunta, HMAS Tobruk, HMAS Swan, HMAS Sydney, HMAS Vendetta and HMAS Vampire and saw service in the Korean War and the Vietnam War.^[1]

On 9 May 1957, he married Shirley McLellan.^[2] Together they had two daughters, Jann a teacher on the North Shore of Sydney, Kay CEO of a recruitment company and a son, Commodore Peter John Sinclair, who joined the navy and was the commander in charge of the commissioning of the Collins class submarines.^[3]

Sinclair's first command was of HMAS Duchess from 1970 to 1972, and then of the Guided Missile Destroyer, HMAS Hobart.^[2] As commander in 1974, his ship was called upon to take part in the relief operations in Darwin, Northern Territory, following Cyclone Tracy.^[4]

Commanding until 1977, Sinclair soon rose to higher administrative and directive roles in the navy, serving as commander of HMAS Penguin in 1978, Director of Naval Plans from 1979 to 1980, Director-General of the Military Staff Branch Strategic and International Policy Division Department of Defence from 1980 to 1982 and Chief of Staff and Deputy to the Naval Support Commander from 1983 to 1984. Sinclair was Chief Project officer during the establishment of the tri-service Australian Defence Force Academy, serving as its first commandant from 1984 to 1986. In the 1986 New Year Honours list, Sinclair was made an Officer of the Order of Australia (AO) for "Service to The Royal Australian Navy, particularly as the First Commandant of the Australian Defence Force Academy".^[5] In 1987 he was appointed Flag Officer Commanding HM Australian Fleet, a position which later changed to Maritime Commander, Australia.^[2]

During the 1987 Fijian coups d'état, Sinclair was in charge of the evacuation of all Australian citizens from Fiji. In 1989, he was appointed as Deputy Chief of the Naval Staff. He served only briefly and in that same year he retired from the Navy to take up cattle breeding at "Kirkbreck" a property near Tea Gardens, New South Wales. In 1990, the Premier of New South Wales, Nick Greiner, asked Sinclair to coordinate the Flood Relief Operations during the Nyngan and Bogan Shire floods.^[6]

When his friend and navy colleague, Sir David Martin, resigned his commission as Governor of New South Wales on 7 August 1990 due to an advancing medical condition, dying three days later on 10 August, Sinclair was the only person considered as Martin's replacement. The Premier of New South Wales, Nick Greiner, identified a military appointment as the only appropriate successor to Martin and recommended Sinclair's to Buckingham Palace. This was accepted by Queen Elizabeth II and Sinclair was sworn in on 8 August 1990. At his swearing in, Sinclair declared that he and his wife would "steer a broad course set by Sir David and Lady Martin". Sinclair later took the advice passed on to him from Martin in his notes: "The person who is Governor is not important. The office of Governor is important."^[6] During his time at Government House, Sydney, Sinclair increased accessibility to the public. While all previous Governors had maintained public access through Garden Parties and specific events, Sinclair was the first to start Government House open days, the first being on 24 March 1991. By the end of his term in 1996 approximately 35,000 people had visited the Vice-regal residence.^[7]

While initially uncertain of his constitutional role, particularly in regard to the Executive Council, Sinclair decreed that all Ministers of the Crown were required to produce a certificate with any legislation requiring assent. The certificate declared that the NSW Crown Solicitor, then Hugh Roberts, had scrutinised the legislation and could therefore recommend assent without problem. While during the Greiner/Fahey Governments, Sinclair received compliance with these requests as well as regular attendance to Council meetings. However, once the Carr Labor Government took power in 1995, Labor ministers were less ready to accede to Crown scrutiny. Sinclair readily took advice from many sources including Chief Justice Murray Gleeson, fellow state Governors and former NSW Governors, Sir Roden Cutler and Sir James Rowland.^[8]

On his retirement, Sinclair returned to "Kirkbreck" but nevertheless continued in public life for the RSL with a life membership, as Chairman of the Council of the Order of Australia from 1996 to 2001, Vice-President of St John Ambulance New South Wales, Deputy Chair of the Newcastle Permanent Building Society, and a Councillor of the ANZAC Health and Medical Research Foundation. In 1992 Sinclair was made an honorary Doctor of Sydney University, and an Honorary Doctor of Southern Cross University in 1996.^[2] In retirement, Sinclair gives regular talks on constitutional matters to various groups and he is Patron of the Hunter Medical Research Institute, Australian Surf Life Saving Foundation.,^[18] Task Force 72 and the Rail Motor Society, Paterson.

On 28 November 2013 the Premier of NSW announced that the Queen had given approval for the title of "The Honourable" to be accorded to the governors and former governors of New South Wales.^[19] In June 2016, Sinclair was called as a witness before the Royal Commission into Institutional Responses to Child Sexual Abuse and gave an account of his experience as a victim of a humiliating initiation ritual when he joined the navy and had vowed to never let the practice happen on his watch, during his time as Deputy Commander at HMAS Leeuwin Naval Base.^[20]