David was elected Speaker of the House of Representatives on 31 January 2013.
He was first elected to Parliament in 1994, was the Junior Government Whip in 1996, before being promoted to a Minister outside Cabinet in 1998. His ministerial responsibilities included Minister for Senior Citizens, Associate Minister for Food Fibre, Biosecurity and Border Control, Associate Minister for Revenue, and Associate Minister for Education. From 1999 he was the National Party spokesman for Finance, Housing, and Tourism. In 2002 he was made the spokesman for Agriculture, and chaired the Primary Production Select Committee. Following the 2008 General Election, David’s ministerial responsibilities included Minister of Agriculture, Minister for Biosecurity and Minister of Forestry. David was appointed Minister for Primary Industries following the 2011 General Election and Minister of Local Government in early 2012.
David attended St Bede's College in Christchurch and graduated with a Bachelor of Agricultural Science degree from Lincoln University before embarking on a farming and business career.
David currently farms sheep and beef properties on Banks Peninsula and at Cheviot in North Canterbury.