Gavin Casey was educated at the Western Australian School of Mines in Kalgoorlie. During the Great Depression of the 1930s he worked as a miner and underground electrician. It was also then that he started his career as a journalist, reporting on Kalgoorlie news. After the Second World War, he became the Director of the Australian News and Information Bureau in New York. On his return to Australia, he worked for the ANIB in Sydney, Canberra and Perth.
In addition to publishing seven novels, Casey was a prodigious writer of short stories. His short fiction which appeared in a number of journals, most particularly the Bulletin, was also published in two selected works, It's Harder for Girls and Other Stories(1942) and Birds of a Feather(1943). In addition to writing fiction, Casey co-authored (with Ted Mayman, q.v.) an informal history of Kalgoorlie, The Mile That Midas Touched (1964), and in 1956 wrote the script for Bones of Building; a safety film that was commissioned by the Building Workers Industrial Union. He also published novels, including Downhill is Easier (1946) and City of Men (1950).
Casey was the foundation secretary of the WA Branch of the Fellowship of Australian Writers. Biographical cuttings/material and manuscripts are held by the NLA (MS2622) and the JS Battye Library (MN295).