Colin was first elected as a Member of the Scottish Parliament for the South Scotland region in May 2016 and re-elected in 2021.
Previous to being elected Colin was a Councillor for the Nith ward on Dumfries and Galloway Council. During his time on Dumfries and Galloway Council he served as the Chair of the Economy, Environment and Infrastructure Committee.
After graduating from the University of Glasgow Colin was a Modern Studies teacher before working for the Scottish Labour Party as an Organiser and latterly as General Secretary.
Upon his election to the Scottish Parliament, Colin was appointed as a Labour Shadow Health Minister and Whip. Colin was then appointed the Scottish Labour Spokesperson for the Rural Economy, Connectivity and Transport. Under Leader Anas Sarwar, Colin was previously Spokesperson for Constitution, Europe and External Affairs and Scottish Labour Shadow Cabinet Secretary for Net Zero, Energy, Transport and Rural Affairs.
In Parliament Colin sits on the Economy and Fair Work Committee and on a number of cross party groups.