Sir John Patrick (Jack) Dwyer KCMG (24 June 1879 – 25 August 1966) was Chief Justice and Lieutenant Governor of the State of Western Australia from 1945 to 1959.
Dwyer was born on 24 June 1879 at Aberfeldy, Victoria, the son of Thomas and Elizabeth Dwyer. He studied at Geelong College where he excelled at cricket and football in addition to his academic work. Dwyer graduated as dux of the school in 1893. In 1897 he attended the University of Melbourne with the intention of becoming an articled clerk.
Dwyer was called to the Victorian Bar in 1902 but relocated to Western Australia in 1904 following an offer of employment with Fremantle barrister (and MP) Matthew Moss. He was admitted to the Western Australian Bar in the same year. In 1908 Dwyer married Emily Louise Munro at St John's Church in Fremantle. After a brief period with Albany law firm Hayes and Robinson he returned to Fremantle as junior partner to Moss in 1911.
Dwyer enlisted with the Australian Imperial Forces on 30 May 1916 shortly after the ANZAC withdrawal from Gallipoli, and was commissioned as a lieutenant a year later. Arriving in France four months before Armistice Day, Dwyer served with the 44th Battalion during the closing stages of the German counteroffensive and in the immediate aftermath of the war itself. He returned to Australia in early 1919 and was officially demobilised on 23 July.