Neil Thomson became the WA Liberal Party member for the Mining and Pastoral Region in the Legislative Council in 2021. Mr Thomson also became the Shadow Minister for Planning, Lands and Heritage. The National-Liberal Alliance was formed in February 2023 and Mr Thomson became the Shadow Minister for planning, environment, lands, heritage. In March 2024, following a cabinet reshuffle, Mr Thomson became the Shadow Minister for Treasury and the Environment.
Prior to politics, Mr Thomson was a partner of ATEA Consulting; executive director at the Department of Aboriginal Affairs for 3 years; and assistant director general at the Department of Planning, Lands and Heritage for over 3 years. He had also held roles at the Department of the Premier and Cabinet in WA, Department of Treasury WA, Department of Fisheries WA, and the Department of Agriculture and Food WA.