Hon. Joseph Docker (1802 – 9 December 1884), was an Australian politician, member of the New South Wales Legislative Council.
Docker was the second son of wool merchant Robert Docker, of London, and Eliza née Perry. Born in 1802, he left school at 13 and was apprenticed to Dr Thomas Docker of Dover, whose daughter Agnes he married in 1830. He became a surgeon in the service of the East India Company.
Docker emigrated to New South Wales (Australia) in 1835 and established himself as a grazier, with 10,000 acres in the Upper Hunter Valley, at "Thornthwaite", near Scone. Agnes died in childbirth, and Docker briefly returned to England. He was married in April 1839 to Matilda, daughter of Major Thomas Brougham, H.E.I.C.S., of Penrith, Cumberland.They returned to Australia together, and subsequently had a daughter and six sons, including Ernest Brougham Docker.
Docker was appointed a member of the Legislative Council (upper house) in New South Wales on 20 May 1856 after being defeated as a candidate for the New South Wales Legislative Assembly seat of Phillip, Brisbane and Bligh. He was a member of the Council until 10 May 1861, and again from 16 December 1863 until 11 December 1884 (his death).
He was twice Postmaster-General: from January 1866 to September 1868 in the second ministry of James Martin, and from December 1870 to May 1872 in Martin's third Ministry. Whilst holding office on the first occasion he introduced and carried through the Upper House Henry Parkes's Public School Bill in 1866. He was briefly Colonial Secretary in the last month of Martin's second ministry. Docker was the Representative of the Government in the Legislative Council on four occasions, in the first and second Martin ministries and in the third and fourth Robertson ministries. Docker was also Minister of Justice and Public Instruction in the third Robertson ministry and Vice-President of the Executive Council in the fourth Robertson ministry.
Docker was one of the three Australian commissioners tasked by the Government of New Zealand with choosing a new capital for that country. Together with Francis Murphy (Victoria) and Ronald Campbell Gunn (Tasmania), he recommended for the capital to move from Auckland to Wellington.
He died on 9 December 1884 (aged 81–82) in Sydney.