Three businessmen who donated large sums to the National Party have had convictions relating to those donations overturned at the Court of Appeal.
The court found the businessmen - Yikun Zhang, and brothers Shijia (Colin) Zheng and Hengjia (Joe) Zheng - did deceive the Electoral Commission and the National Party secretary, but the Serious Fraud Office (SFO)'s evidence was unable to show they personally benefited from the donations.
However, Joe Zheng's conviction and sentence for lying to the SFO - obstructing their investigation - remains in place.
The trio were sentenced to community detention in November 2022, after the High Court found them guilty on charges of obtaining by deception brought by the SFO.
They had split donations to the National Party - of $100,000 in 2017, and $100,050 in 2018 - into smaller donations of under $15,000 each under the names of several people, enabling them to avoid having to declare the donations publicly.
However, the Court of Appeal judges said the SFO's argument that it was enough to show National had benefited, rather than the businessmen, fell short.
"There is no doubt that the National Party Secretary and/or the Electoral Commission were deceived by the appellants. The only issue in relation to charges 3 and 5 is whether the appellants obtained a benefit directly or indirectly," their judgement said.
The court found the law as written requires that the defendant must benefit, they said.
"The SFO did not attempt to argue before us that the appellants obtained a benefit. Instead, the SFO continued to argue that it was sufficient for the National Party to obtain the benefit."
The judges, however, said they were satisfied the evidence clearly showed Joe Zheng had lied to the SFO in three ways, and said High Court Judge Gault's reasons for concluding Zheng had deliberately set out to mislead the SFO were "unimpeachable".
In a statement, the SFO said the case had been an important one to bring to court "for the integrity of New Zealand's electoral system and our reputation for transparency".
"New Zealand's response to any behaviour that may undermine our electoral systems is essential to preserving our reputation as one of the least corrupt countries in the world. The SFO is tasked with safeguarding that reputation and it is a role we take very seriously," the statement said.
"With no applicable offence under the Electoral Act, the charge of obtaining by deception most appropriately captured the seriousness of the alleged offending. However the Court of Appeal considered the charge of obtaining by deception could not apply as the appellants had not personally obtained a benefit.
"We note that an Independent Electoral Review Panel is carrying out a review of New Zealand's electoral law."
Joe and Colin Zheng had both initially sought to appeal their sentences, but abandoned that before making their case. The court said because they were allowing Yikun Zhang's appeal against conviction, it was not necessary to deal with his sentence.
Zhang and the Zhengs and three other people - who have name suppression - were also charged over donations to the Labour Party, but were found not guilty by the High Court last year, and former National Party MP Jami-Lee Ross was also found not guilty.
The case came to public attention after Ross publicly claimed then-National leader Simon Bridges had asked him to collect and split a large donation to avoid disclosing the donor.
Ross went to the police with what he claimed was evidence of this, but Bridges was never charged and - during the court trial - agreed Ross had been "going full kamikaze".
Ross's lawyer told the court his client had lied to the SFO in an effort to implicate Bridges, seeking revenge after he felt Bridges had not promoted him as expected.