In 2016, Newton, alongside her five cousins and other supporters, formed the group Save Our Unique Landscape (SOUL) to protest the development of land at Ihumātao, which had been taken from Māori ownership in 1863. She has said they were inspired by
Whina Cooper and other Māori women protestors. Although Newton was the youngest of the six cousins, she became the spokesperson and lead of the campaign. She led the occupation of the land during the peaceful protests and herself lived in a caravan for over three years. Newton and the other protestors living at the site faced opposition from Fletcher, which issued them trespass notices in 2016 and attempted to demolish a farmhouse on the property in 2017. Newton visited the United Nations on two other occasions to advocate for the cause. Following her first visit, in August 2017, a United Nations report said that the government had not adequately consulted with the local iwi, and recommended that the government re-evaluate whether the plan was compliant with the
Treaty of Waitangi and the
United Nations Declaration on the Rights of Indigenous People. In November 2018, Newton and others lost an appeal to the
Environment Court seeking that the development be blocked. Later that month, a group of about 30 protestors including Newton attended Fletcher's annual general meeting to protest against the development. She did however meet with the minister for Māori development,
Nanaia Mahuta, on 31 July 2019, and described it as a positive meeting. As a result of the increased media attention, the protest grew by hundreds of people with visitors to the site that drew public figures
Stan Walker,
Ladi6 and others. Police presence at the site increased in early August 2019. On 5 August a standoff with police took place; Newton said police had rammed her with a gate as she was seeking to protect minors on the protest frontline, which police denied. The police presence was ultimately reduced on 16 August. Later that month, she and other protestors undertook a
hīkoi (protest march) to the prime minister's Auckland office, where they delivered a petition asking Ardern to visit the land. In December 2019, Newton announced that she was pregnant and that her baby would be born at Ihumātao. In February 2020,
Heritage New Zealand announced that the area had been given the highest heritage status category, but Newton said the change was largely symbolic as it did not prevent development from going ahead. In March 2020, shortly after her daughter was born and with the start of
New Zealand's COVID-19 lockdown, she was one of thirty people remaining on the land, and said that they would isolate together. She noted that the negotiations about the future of the land between the government, the
Kīngitanga movement and the council had been put on hold due to COVID-19. In December 2020 the government purchased the land from the developer, with the intention of using it for housing. Newton said she was keen to ensure discussions continued about preserving the cultural heritage of the land. a planned steering committee to examine future land use was still in the process of being appointed, and
The New Zealand Herald reported that a decision on the future of the land could be up to five years away. At that time, Newton continued to live on the land with her daughter. ==Recognition and other activities==