Member of the Scottish Parliament
In 2016, Greene stood for the Scottish Parliament as the Conservative candidate for the Cunninghame North constituency where he came second, then as second on the West Scotland regional list for the Scottish Conservatives.[3][4] He stood again in 2021, achieving 10,451 votes, an increase of 3.5% from the 2016 election, though failed to be elected. He was instead reelected on the West Scotland regional list.
Greene was appointed as Shadow Cabinet Secretary for Justice in the current term of Parliament, later replaced by Russell Findlay in a reshuffle, and previously served as Shadow Cabinet Secretary for Education and Skills and Shadow Cabinet Secretary for Transport, Infrastructure and Connectivity.
He is Deputy Convenor of the Public Audit Committee and Deputy Chair of the Scottish Commission for Public Audit, a non-parliamentary board which oversees Audit Scotland.
Prior to this he held roles as the Scottish Conservative spokesperson for transport and infrastructure, technology, connectivity and the digital economy as well as digital broadcasting.[5] He sat on the Education and Skills committee having previously sat on the Rural Economy and Connectivity Committee, the Equalities and Human Rights and Culture, Tourism, Europe and External Affairs Committees respectively of the Scottish Parliament.[6]
After his election in Term 5 of the Scottish Parliament (2016–21) he also instigated and was Co-Convenor of the Scottish Parliaments' first Cross-Party-Group (CPG) on LGBTI+ issues. He is also Convenor of the CPG on Taiwan. An active member of the Commonwealth Parliamentary Association (CPA) he has represented the Scottish Parliament on a number of engagements serving in parliamentary training and election monitoring and observing functions.
Greene initially expressed an interest in standing for the 2020 Scottish Conservative & Unionist Party Leadership Election, but announced in January 2020 that he was dropping-out to support incumbent acting-leader Jackson Carlaw who was later replaced by Douglas Ross.
Greene announced that he would run in the Scottish Conservative Leadership election to replace Douglas Ross, who announced he would stand down after the 2024 General Election. Greene removed himself from the leadership contest prior to nominations closing and subsequently endorsed Murdo Fraser for the leadership.
Resignation from the Conservatives and subsequent activity
On 3 April 2025, Greene left the Conservative Party in protest of Russell Findlay's leadership, claiming the party had adopted a "Reform-esque agenda" and "Trump-esque narrative" under Findlay that risked marginalising the party as it abandoned the centre ground.[7][8] The next day, Greene joined the Scottish Liberal Democrats.[9] He was later appointed front-bench spokesperson for Finance and the Economy for the Liberal Democrats.
Greene sought election in the 2026 Scottish Parliament election.[10] In October 2025, he was selected as the Liberal Democrat candidate for Inverclyde.[11][12]
On the regional list, Greene was placed second.[13]
