David Seymour

David Breen Seymour (born 24 June 1983) is a New Zealand politician who has served as the 21st deputy prime minister of New Zealand since 2025 and as the 1st minister for regulation since 2023. A member of the ACT Party, he has served as its leader and as the member of parliament for Epsom since 2014. Typically classified as a right-libertarianpopulist, Seymour has liberal views on freedom of choice and economic policy, and conversely majoritarian and reactionary views on New Zealand civic nationalism and indigenous rights.

Seymour spent his early years in Whangārei and joined the ACT Party while studying at the University of Auckland. Following his graduation in 2006, he worked in the engineering industry. Subsequently, he worked for conservative think tanks in Canada during the 2000s, and was linked to the Atlas Network. He stood unsuccessfully for election to the New Zealand House of Representatives in 2005 and 2011, before being elected in 2014 as ACT's sole MP. He then replaced Jamie Whyte as party leader.

Seymour was re-elected in 2017, returning as ACT's sole MP. In 2020, he led ACT to one of its best results in the general election, winning ten seats and retaining his Epsom electorate. He was chiefly responsible for the End of Life Choice Act 2019, which decriminalised euthanasia in New Zealand via referendum in 2020. In the 2023 general election, Seymour was re-elected and the ACT Party increased its representation to 11 seats. This was the best result in the party's history, with the party picking up an extra electorate seat in Tāmaki. ACT subsequently formed a coalition government with the National and New Zealand First parties. Under the coalition arrangement, the position of deputy prime minister was split between Winston Peters and Seymour. Peters served until 31 May 2025, when he was succeeded by Seymour.

Seymour's views on the principles of the Treaty of Waitangi and the ACT Party's Treaty Principles Bill have led to major controversy in New Zealand. He is a strong opponent of co-governance with Māori, and as part of the current government he and ACT have proposed major changes to the principles through reinterpretation of the original Māori text of the Treaty of Waitangi. This includes the removal of any references to "partnership (co-governance)" (between the Crown and Māori) from the treaty's use in law and instead refer to "all New Zealanders". As per the coalition agreement, National and New Zealand First supported the bill to select committee. Ultimately, the bill was voted down on its second reading on 10 April 2025 by a vote of 11–112, with all ACT MPs voting in favour of the bill. Backlash to the proposals led to the Hīkoi mō te Tiriti, which formed one of the largest protests in New Zealand history.