In the provincial elections of August 1853, Moorhouse stood in the Akaroa electorate for one of two positions on the Canterbury Provincial Council. There was a draw for second place and the returning officer gave his casting vote to the other candidate, Rev. William Aylmer. A week earlier, Moorhouse had stood in the same electorate for the House of Representatives and had been successful. In 1855, Moorhouse was first elected to the Canterbury Provincial Council. From March to July 1855, he represented the Akaroa electorate on the first Council. He later served as the Province's Superintendent after James FitzGerald resigned from the superintendency in October 1857 due to illness. Moorhouse and Joseph Brittan contested the vacancy, and obtained 727 and 352 votes, respectively.