Brendan Horan claims New Zealand First is using taxpayer-funded software to recruit members and raise funds.
Horan, who was kicked out of the NZ First caucus last year and yesterday referred to as "Jimmy Savile" by NZ First leader Winston Peters, said the software titled "vanguard" was a constituent relationship management system which stored voter details.
Using parliamentary privilege, Horan alleged that the party had "paid tens of thousands of dollars out of the Leader's Budget to develop this software and has their Parliamentary staff are working to run the programme for election year. This is a clear breach of Parliamentary Service guidelines."
Horan said that other parties had similar systems, but fund the software themselves and operate it independently of Parliament.
He pointed to a company, Lone Star Market Research, whose sole director is a NZ First staff member, which Horan claims was set up with the intention "of conducting political activity" for New Zealand First. He said New Zealand First needed to give an assurance that "not one cent" of taxpayer funding went into it.
Horan claimed another staffer who works as an out-of-Parliament secretary in Whangarei was the party's membership secretary.
"This is a clear conflict of interest."
Horan said: "This use of Parliamentary Resources for funding appeals and political campaigning is more than questionable, especially from that party, which promised in the last election a fair go. The public have a right to know what their money is being used for and whether it is being used legally."
He claimed to have a paper trail which "leads down the pathway to inappropriate use of public monies, serious conflicts of interest, secrecy and a lack of transparency, and accountability, all from a party which purports to hold everyone else to task."
After his speech he attempted to table a series of documents but was blocked from doing so by NZ First MPs.
During the speech a number of New Zealand First MPs attempted to prevent the speech from being made under standing orders, but Acting Speaker Lindsay Tisch ruled that it was appropriate as it was the Budget speech and Horan was debating Parliamentary Service appropriate.
Barbara Stewart said the speech was "totally incorrect, just fantasising" and that the Vanguard software had not been launched.
Within seconds of the speech being completed, NZ First issued a one-line statement.
"New Zealand First says the accusations made in Parliament today by independent member Brendan Horan are baseless and without foundation."
Peters said this afternoon that the allegations were "totally baseless" and he was "totally confident" that there was nothing improper about his use of the leader's budget.
Peters confirmed that Vanguard existed, but had not been launched. It had been purchased using taxpayer funds "just like any other political party that has computer systems and software to enable them to communicate with sector groups all around the country".
He denied the party's out of Parliament secretary in Whangarei had any conflict of interest, as she was only working part time in the role. "She has every entitlement to use the remainder of her time to work on party issues in her private time."
Peters said Horan was "a desperate man on his way out of politics".
The party did not plan to take retaliatory action.
"Elephants don't go running around the forest stomping on ants, do they?"
However he confirmed he was taking action against Horan alleging defamation, relating to an interview with Radio New Zealand last week. Radio New Zealand has already offered an apology to Peters over the interview.
"What we seek to get is the truth out there. We're not putting up with lies."
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