On 6 May 1868[3] Langton, who was a staunch Conservative as well as a Free-trader, became Treasurer of Victoria in Charles Sladen's short-lived Ministry, and occupied the same post, with the additional office of Postmaster-General of Victoria, in the James Francis Government, from 10 June 1872 to 31 July 1874,[3] when he resigned with his colleagues.[2] Langton has written much for the Melbourne press, and was one of the earliest proprietors of the Spectator, a free trade organ started in 1865. He was secretary of the Free Trade League of Victoria from its commencement until 1866, was an honorary member of the Cobden Club from 1874, and was a trustee and treasurer of the Melbourne Public Library and Museum.[2]
Langton was again unsuccessful in contesting Castlemaine February 1880, West Melbourne in 1886, Toorak in 1892 and 1894, and East Melbourne in 1897.[3]
Langton died of pneumonia on 5 October 1905 in his home in Toorak, Victoria;survived by a daughter and one of his two sons.[1]