He was educated at Craigmount High School and Stevenson College.

Between 2007 and 2012 he was a councillor for Drum Brae/Gyle ward on The City of Edinburgh Council.

[3] Keir contested the seat of Edinburgh Western in the 2011 Scottish Parliament election, and defeated the Liberal Democrat incumbent Margaret Smith with a substantial swing to win with a margin of 2,689 votes.

[4] In August 2015, after serving just one term, Keir was defeated in his attempt to be re-nominated as the SNP candidate in Edinburgh Western for the 2016 election.

Keir was beaten by Toni Giugliano, a member of the party's national executive committee, who had received the backing of former leader Alex Salmond.