"Member of the New South Wales Legislative Assembly for Darling Downs — In office 5 July 1859 – 10 December 1859 — Serving with William Handcock"
Infobox term dates. The ADB corroborates: "Douglas represented the Darling Downs in the New South Wales Legislative Assembly from July to December 1859; 'As a liberal in heart as well as in principle' he generally supported the premier, Charles Cowper".
"Member of the New South Wales Legislative Assembly for Camden — In office 21 December 1860 – 17 July 1861"
Infobox term dates. The ADB corroborates: "In December 1860 he re-entered politics, holding the second seat for Camden until he resigned on 17 July 1861."
"Member of the Queensland Legislative Assembly for Port Curtis — In office 14 June 1863 – 1 February 1866" ... "He resigned on 1 February 1866, in order to be appointed on to the Queensland Legislative Council, which occurred on 22 February 1866."
Infobox dates plus the article body. The ADB corroborates: "Douglas moved to Brisbane in 1863 and was elected for Port Curtis to the Queensland Legislative Assembly where he remained independent of the Herbert ministry."
"Member of the Queensland Legislative Council — In office 22 February 1866 – 25 July 1866" ... "He resigned on 1 February 1866, in order to be appointed on to the Queensland Legislative Council, which occurred on 22 February 1866."
Infobox dates plus article body. ADB corroborates the leadership role: "postmaster-general from 1 March to 20 July and leader of the government in the Legislative Council".
"Member of the Queensland Legislative Assembly for Eastern Downs — In office 4 January 1867 – 18 September 1868 — Preceded by John Donald McLean — Succeeded by Arthur Macalister"
Infobox dates. The ADB corroborates the seat and the land-bill role: "In 1867 he was elected for the Eastern Downs." and "As an ardent advocate of the pro-agriculturist provisions in the land bill of 1867, he strongly attacked squatters for their practice of dummying on the Darling Downs, and was appointed chairman of a select committee."
"Member of the Queensland Legislative Assembly for East Moreton — In office 28 September 1868 – 16 December 1868 — Serving with Arthur Francis — Preceded by James Garrick — Succeeded by Henry Jordan"
"Member of the Queensland Legislative Council — In office 11 December 1868 – 13 November 1869"
Infobox second Council term. The ADB corroborates the leadership: "when the liberal (Sir) Charles Lilley became premier Douglas held office as postmaster-general from 12 December to 13 November 1869 and moved into the Legislative Council as leader of the government".
"Member of the Queensland Legislative Assembly for Maryborough — In office 27 April 1875 – 24 November 1880 — Serving with Henry King — Preceded by Berkeley Basil Moreton — Succeeded by Henry Palmer"
Infobox dates. ADB corroborates the earlier defeats and the breach of privilege: "After his return from England Douglas was easily defeated for East Moreton in November 1871, narrowly lost the Brisbane seat in November 1873 and was just beaten for Darling Downs in March 1875" and "Always obstinate Douglas was found guilty of 'a very extraordinary breach of privilege' in 1880. He sent to the Brisbane Courier information given to a select committee despite standing orders which forbade publication before evidence was reported to parliament" and "he refused to apologize even after the assembly had voted that he was guilty of contempt".