Crozier was born in Roxburgh, Scotland, and in 1838 emigrated in the Coromandel to New South Wales, where he had been appointed to manage the estate of Redesdale, in the Braidwood district, owned by Dr. Anderson, of Parramatta, and which was principally worked by assigned convicts.
After some years of this pioneering work, Crozier became the sole proprietor of Kulnine, and eventually prospered sufficiently to acquire Moorna and other stations on the opposite side of the Murray.
Eventually he sold Kulnine station and half the stock to Mr. Bagot, and as years went on he purchased runs in the north and on the Queensland and New South Wales borders, placing his sons in charge of these properties.
Three seats had become vacant through death or resignation, and Crozier was returned at the head of the poll, with (later Sir) William Morgan and Emanuel Solomon the other successful candidates.
In 1877 six elected members were returned: William Morgan, John Crozier, Richard Chaffey Baker, Thomas English, James Pearce and Henry Kent Hughes.