Grant West, who was abused as a 6-year-old in Wellington, contacted ODT Insight to take issue with the expanded scope of the upcoming Royal Commission into historic abuse announced this week.
Ms Ardern and Internal Affairs Minister Tracey Martin on Monday confirmed the inquiry would go beyond the abuse of children in state-based care to include children abused while in the care of faith-based institutions as well.
But exactly what was covered or excluded by the term ''in the care of'' remained unclear, prompting concerns from faith-based survivors and their supporters that many victims could yet be left out.
Ms Ardern told Monday's post-Cabinet press conference the inquiry's focus reflected submissions calling for an expanded inquiry, but also the ''original request'' for an inquiry from victims who were in state care.
''The original request came very clearly from those in state care,'' she told media.
Mr West disputed that, saying his own request for a wider inquiry in 2016 pre-dated an open letter from the Human Rights Commission - calling for an inquiry into abuses in state care - published in 2017.
Mr West was living in Australia when he helped push for an inquiry into child sex abuse there, eventually leading to the launch of the Royal Commission into Institutional Responses to Child Sexual Abuse in 2013.
In 2016, while still living in Australia, he returned to New Zealand and travelled around the country, gathering 2766 signatures on a petition calling for the same sort of inquiry in New Zealand.
Among those to support his New Zealand petition was Judge Carolyn Henwood, the chairwoman of New Zealand's earlier Confidential Listening and Assistance Service (CLAS), which provided a forum for victims of abuse in state care.
Mr West's petition was presented to MPs on the steps of Parliament and referred to the Justice select committee, which reported back in December 2017.
The report noted the new coalition Government planned to establish an inquiry into abuse in state care in its first 100 days, which would be an ''appropriate forum''.
Mr West feared the expanded Royal Commission announced this week would not include all victims of faith-based institutions, ''even though they were abused by a person employed by a faith-based institution''.
He believed Ms Ardern had ''misinformed'' the public by suggesting the first plea for an inquiry came from state wards, and this week's announcement ''mocked those survivors of religious institutions''.
A spokeswoman for Ms Ardern, who is in Singapore, would only say the Prime Minister had been ''deeply moved by many pleas from survivors of childhood abuse for an opportunity to be heard''.
''She wants both the state, and faith-based institutions, to learn from the mistakes of the past, to ensure no child is ever abused or mistreated in their care again.''
The Royal Commission is expected to review the terms of reference to decide what was in and out of scope, before hearings began next year.
