Other commentators argue that the Governor General acted improperly in 1975 as Whitlam still retained the confidence of the House of Representatives, and there are no generally accepted conventions to guide the use of the Governor General's reserve powers in this circumstance.[4] . However, there is no constitutional requirement that the Prime Minister sit in the House of Representatives, or even be a member of the federal parliament (subject to a constitutionally prescribed limit of three months), though by convention this is always the case. The only case where a member of the Senate was appointed Prime Minister was John Gorton, who subsequently resigned his Senate position and was elected as a member of the House of Representatives (Senator George Pearce was acting Prime Minister for seven months in 1916 while Billy Hughes was overseas; and Senator Mathias Cormann acted for a few days in February 2018 while Malcolm Turnbull was overseas).[5][6]