Seymour and van Velden developed a "sponsor's report" for the bill, giving their own recommendations before the committee, including limiting assisted death only to those who were terminally ill.

[13] Van Velden was selected as ACT's deputy leader in June 2020, at the age of 27, and was placed second on its party list for the 2020 general election.

[5][16] In addition to being deputy leader, she is the ACT party whip and spokesperson for Health, Housing, Foreign Affairs, and Trade.

[17][18] In late April 2021, van Velden submitted a motion asking the New Zealand Parliament to debate and vote on the issue of human rights abuses against the Uyghur ethnic minority community in China's Xinjiang province.

[19] In early May, the incumbent Labour Party revised the motion to raise concerns about human rights abuses in Xinjiang while deleting the term genocide, which was subsequently adopted by the New Zealand Parliament on 5 May.

Van Velden justified ACT's opposition on the basis of another Green MP Ricardo Menéndez March's tweet that said "From the river to the sea, Palestine will be free!."

[32] As Workplace Relations Minister, she introduced legislation repealing the previous Labour Government's Fair Pay Agreements Act 2022 on 19 December 2023.

"[34] On 1 February 2024, van Velden, as Workplace Relations and Safety Minister, confirmed that the Government would raise the minimum wage by two percent to NZ$23.15 an hour from 1 April 2024.

[36] As Workplace Relations Minister, van Velden confirmed that the Government was planning to overhaul health and safety regulations and amend the Holiday Act 2003.

[38] Van Velden has stated her reasons for entering politics are to reduce generational debt, improve housing affordability, and provide better mental health for all.

[40] She was formerly a Green Party voter but switched to supporting ACT while studying economics and international trade at the University of Auckland.