Public life
O'Connor was active in Sydney public life in the 1870s, being a member of the Catholic Association, chair of the Catholic Truth Society and vocal in his support of pardoned Fenian prisoners. In 1876 he was elected to the Phillip Ward of the Sydney City Council. Apart from a brief period in 1879, he represented the ward until 1885.
O'Connor was elected to the West Sydney electorate of the New South Wales Legislative Assembly in 1877. As a member of Parliament he was an opponent of Chinese immigration and payment of Members of Parliament. In December 1885 O'Connor was appointed Postmaster-General in the fifth Robertson ministry, a role he served in for just over two months, until the ministry fell in February 1886. He joined the Free Trade Party with the emergence of political parties at the 1887 election. He was again appointed Postmaster-General in March 1889 in the fifth Parkes ministry, serving for over two and a half years.
After serving eight terms and almost 14 years in the Legislative Assembly he lost his seat of West Sydney in the 1891 election that saw the emergence of the Labour Party, winning all four seats in West Sydney. He was subsequently appointed to the New South Wales Legislative Council.
While still in Parliament, O'Connor went into business with sometime-politician John Hurley. In 1892 the business collapsed, forcing O'Connor, and Hurley, to declare bankruptcy. As a bankrupt he had to give up his seat in the Legislative Council. He was reappointed in 1895, serving until his resignation in July 1898 when he attempted to regain a seat in the Legislative Assembly switching to Edmund Barton's National Federal Party.
O'Connor was elected to the Legislative Assembly seat of Sydney-Phillip at the 1900 by-election on a Protectionist ticket, retaining the seat in 1901. He served the electorate until 1904 when he finally withdrew from public life.
