He was elected to the Scottish Parliament in 2003 aged 29, making him the youngest constituency MSP at the time.

He was re-elected in 2007 following a close campaign, with some of the media stating that the Scottish National Party candidate Christine Grahame would defeat him.

Ultimately, both parties greatly increased their vote shares at the expense of the Conservatives and Labour.

He was created a life peer on 13 September 2013 taking the title Baron Purvis of Tweed, of East March in the Scottish Borders.

[2] In November 2016 he was announced as a member of the Commission on Parliamentary Reform, having been nominated to represent the Scottish Liberal Democrats.