Duncan Webb

First term, 2017–2020 In Webb's first term of Parliament, he served on various select committees including Regulations Review (2017–2020), Foreign Affairs, Defence and Trade (2017–2018), Justice (2018–2019), Finance and Expenditure (2017–2020) and Environment (as chair, 2019–2020).

Second term, 2020–2023 During the 2020 New Zealand general election, Webb was re-elected in Christchurch Central, defeating National candidate Dale Stephens by 14,098 votes. On 2 November 2020, following the election, he became one of three junior whips for the Labour Party and was also appointed chair of the Finance and Expenditure select committee. After a June 2022 Cabinet reshuffle, in which senior whip Kieran McAnulty became a minister, Webb was promoted to senior whip.

A private Bill on behalf of the Girl Guides Association (New Zealand branch), which was concerned with the disposition of property held by the association in Waitākere, was introduced by Webb in 2021. However, the social services committee recommended it not proceed. Webb's second member's bill, the Companies (Directors Duties) Amendment Bill, was introduced to the House on 23 September 2021. The purpose of the Bill is to make it clear that company directors can take actions that take into account wider matters other than the company's finances.

On 31 January 2023, prime minister Chris Hipkins announced a Cabinet reshuffle, in which Webb was appointed a Minister outside of Cabinet, with the portfolios of commerce and consumer affairs and state owned enterprises. He held these positions until the government left office in November 2023. As commerce minister, Webb took responsibility for work regulating the supermarket industry. He appointed the first New Zealand Grocery Commissioner and instituted unit pricing regulations. With finance minister Grant Robertson, he announced a market study of the banking sector. As minister for state owned enterprises, he instituted reviews into KiwiRail disruptions and weather forecasting.

Third term, 2023–present Webb was re-elected in Christchurch Central for a third time in October 2023, defeating Dale Stephens by a decreased margin of 1,841 votes. He is currently the Deputy Shadow Leader of the House and holds the justice, regulation, Earthquake Commission, and Christchurch Issues portfolios in the Shadow Cabinet of Chris Hipkins.

On 5 December 2023, Webb was granted retention of the title The Honourable, in recognition of his term as a member of the Executive Council.

Following a shadow cabinet reshuffle on 7 March 2025, Webb lost his Christchurch Issues portfolio but retained his other portfolios. On 21 October 2025, Webb announced that he would retire from politics at the 2026 New Zealand general election.

On 25 November, Webb lodged a member's bill to repeal the Regulatory Standards Act 2025, and reiterated the party's commitment to repealing the legislation within its first 100 days of forming a new government if it won the 2026 general election.

In May 2026, Webb was part of a cross-party delegation of four New Zealand MPs including Maureen Pugh, David Wilson and Laura McClure who visited Taiwan, meeting with Taiwanese legislators and foreign ministry officials. In response, the Chinese government in early June 2026 banned the four from visiting China, Hong Kong and Macau for a year on the grounds that their actions violated the One China policy. The Chinese Embassy in New Zealand stated that their travel ban could be waived if they apologised for their actions. In response, Webb said that New Zealand valued democratic institutions and the right to engage with international partners, stating "If the cost of doing that is to be excluded from China for a year, I will pay that price." He voted in favour of the End of Life Choice Bill in 2019 and Abortion Legislation Bill in 2020.

Treaty of Waitangi Dr Webb has stated that the Treaty of Waitangi is a fundamental part of New Zealand law, emphasising the importance of recognising and accepting the principles of the Treaty as integral to the nation's legal framework.

Social justice Webb consistently advocates for government action to support those in need and for policies that promote a high-wage, low-carbon economy, reflecting his broader commitment to social justice and long-term planning for New Zealand’s future.

Climate change As an MP and minister, Webb has played key roles in advancing climate change legislation and resource management reform, advocating for policies that balance economic growth with environmental sustainability. In early June 2018, Webb also presented a petition on behalf of Palestinian solidarity activist Donna Miles that asked Parliament to request the New Zealand Superannuation Fund to divest from "illegal" Israeli settlements in the West Bank. In August 2018, Webb hosted a meeting with Unite Union Director Mike Treen, who participated in the International Freedom Flotilla's attempt that year to breach the Israeli blockade of the Gaza Strip. Webb's Palestinian activism has drawn criticism from Zionist advocacy groups including the Israel Institute of New Zealand (IINZ), the Australia/Israel & Jewish Affairs Council (AIJAC), and the New Zealand Jewish Council.

On 11 May 2021, Webb and 16 other New Zealand Members of Parliament donned keffiyeh to mark World Keffiyeh Day.

Despite his vocal support for the Palestinians, Webb expressed disagreement with the use of the controversial chant "From the river to the sea, Palestine will be free." The chant has been alleged to be associated with anti-Semitism and support for Hamas. Following controversy around Green MP Chlöe Swarbrick's use of the phrase during a Palestinian solidarity rally held in response to the Gaza war in November 2023, Webb said "he didn't participate if the chant started at rallies he attended."

In early August 2024, Webb attracted controversy after posting an Instagram video where he spoke at a rally where protesters chanted "Hey, Luxon, what do you say? How many kids did you kill today?." Webb also gave a speech denouncing the "demonisation" of Palestinians, alleged "Israeli apartheid," and calling for an end to the Gaza war. While Labour leader Chris Hipkins initially defended Webb, he subsequently expressed disagreement with the chants used during the protest. In response, National Party leader and Prime Minister Luxon denounced Webb's behaviour as "beyond the pale" and labelled Hipkins a hypocrite for not taking stronger action against Webb.