Career
He was elected in the 2011 Parliamentary elections, having previously contested the Ayr Constituency in the 2003 Scottish Parliament elections and the Glasgow South-West Constituency in the 2005 United Kingdom general election before his election in 2011. He was also selected to be the Scottish National Party candidate in the 2009 Glasgow North East by-election, but decided to step aside following newspaper reports over his finances. He represented the Langside Ward in Glasgow City Council from 3 May 2007 until 3 May 2012 and was the Scottish National Party group leader on Glasgow City Council until June 2011, when he was succeeded by Councillor Allison Hunter.
Dornan joined the Scottish National Party in 1996 and previously worked for Stewart Maxwell (Managing Successful Programmes).
In 2012, Dornan was appointed as a Scottish National Party Deputy Whip.