In opposition, 2013–2017 Parekura Horomia, MP for
Ikaroa-Rāwhiti since 1999, died on 29 April 2013. A
by-election to fill his seat took place on 29 June of that year. Whaitiri defeated five others for the Labour nomination, including
Hastings district councillor Henare O'Keefe, broadcaster Shane Taurima and
Ngāti Kahungunu board member Hayden Hape. Most political analysts predicted that Labour would hold Ikaroa-Rāwhiti, which Horomia had held since its formation for the . At his last election in 2011, Horomia had won a majority of 6,541 votes. Whaitiri won the by-election with a majority of 1659 votes over
Mana Party candidate Te Hamua Nikora.
Māori Party candidate Na Raihania, who had also been endorsed by
National, came third. Right-wing political blogger
David Farrar called the by-election a "good victory for Labour", and commented that Whaitiri "could be one of the better Labour MPs". Whaitiri retained Ikaroa-Rawhiti during the
2014 New Zealand general election by a margin of 4,673 votes. As an opposition MP for her first two terms, she was Labour Party spokesperson on water (2014–2015) and local government (2015–2017), and a member of the Māori affairs, primary production, and local government and environment select committees.
In government, 2017–2023 During the
2017 general election, Whaitiri retained her Ikaroa-Rāwhiti electorate seat for the Labour Party by a margin of 4,210 votes. Following the 2017 election, Labour formed a
coalition government with
New Zealand First and the
Green Party. Whaitiri was
Minister of Customs outside Cabinet. She also served as Associate Minister for Agriculture, Forestry, Local Government and Crown/Māori Relations. Alongside
Willie Jackson, she co-chaired the Labour Māori Caucus. From July 2019 until the end of the term, she chaired the Justice select committee. During the
2020 general election, Whaitiri retained her seat of Ikaroa-Rāwhiti by a margin of 6,045 votes. Following the election, she was reappointed as Minister of Customs and Associate Minister of Agriculture (with responsibility for animal welfare) while being appointed as
Minister for Veterans and Associate Minister of Statistics. She additionally became
Minister for Food Safety in June 2022 and the lead
cyclone recovery minister in Hawke's Bay after
Stuart Nash was dismissed from that role in March 2023.
Defection from Labour On 3 May 2023, Whaitiri announced that she had officially notified the
Speaker of the House that she had resigned from the Labour Party and was joining
Te Pāti Māori (the Māori Party). She replaced Heather Te-Au Skipworth as Te Pāti Māori's candidate for her electorate at the
2023 New Zealand general election. During her resignation speech, she attributed her decision to defect to her commitment to Māori political activism. Whaitiri's defection was welcomed by Te Pāti Māori co-leader
Debbie Ngarewa-Packer and President
John Tamihere. Prime Minister
Chris Hipkins learned about Whaitiri's defection after landing in London to attend the
coronation of King Charles III. Some commentary around Whaitiri's defection, including from Māori development minister
Willie Jackson, focused on her apparent disappointment in not receiving a promotion into Cabinet in Hipkins' earlier reshuffles. Also on 3 May,
Speaker of the House Adrian Rurawhe confirmed that Whaitiri would serve until the election as an independent member of Parliament under standing order 35.5, which avoids the
waka-jumping provisions of the
Electoral (Integrity) Amendment Act 2018 from being invoked. Rurawhe's decision not to invoke the waka-jumping law was criticised by
National Party MPs
Michael Woodhouse,
Chris Bishop, and
ACT Party leader
David Seymour. On 4 May, Rurawhe distinguished the Electoral Act from parliament's standing orders, stating that he had not received from Whaitiri a letter of resignation from Labour, despite her public statements, with the result that Whaitiri remained a Labour MP under electoral legislation, but was an independent MP for parliamentary purposes under standing orders. On 10 May 2023, Te Pāti Māori leaders Ngarewa-Packer and Waititi staged a
haka to welcome Whaitiri to their political party. Speaker Rurawhe ordered Ngarewa-Packer and Waititi to leave Parliament since they had not received permission from him or other parliamentary parties to hold the haka. Whaitiri stated that she was "joining a party that doesn't censor the voice of wāhine Māori (Māori women) ... I am joining a party that enables the voice of wāhine Māori to be heard, for our people to celebrate being Māori, unashamedly Māori". Whaitiri stood as the Te Pāti Māori candidate in the Ikaroa-Rāwhiti electorate for the
2023 New Zealand general election and was defeated by Labour's candidate
Cushla Tangaere-Manuel by a margin of 2,843 votes. ==References==