The Solicitor-General says he is considering whether he will take over the case to prosecute ACT Party leader John Banks.
At the Auckland District Court on Wednesday a judge committed Mr Banks to trial on a charge he filed a false return after the 2010 Auckland mayoral election.
Judge Phil Gittos ruled that Mr Banks must face trial over his failure to disclose donations made to his mayoral campaign by casino operator SkyCity and internet businessman Kim Dotcom.
Solicitor-General Michael Heron has written to retired Wellington accountant Graham McCready, who brought the private prosecution, saying he is now reconsidering his early decision not to prosecute.
Meanwhile, Mr Banks says he is confident he has done nothing wrong and is still considering his legal options. "I'm a born optimist and I'm a fighter."
Turei kicked out of House
Green Party co-leader Metiria Turei was kicked out of Parliament on Thursday as tempers frayed during questions about John Banks.
But she was back just an hour later to lead a snap debate on Mr Banks' resignation as a minister.
Opposition parties used Question Time and the debate to criticise Mr Banks' conduct and the Government's support for him.
Ms Turei was ejected from Parliament after repeatedly asking the Speaker David Carter why he had ruled one of her questions out of order.
She returned later to say Mr Banks' case was "an issue of honesty, an issue of credibility and that has had a very significant and very negative effect on this Government."
Ms Turei had earlier suggested the Government should delay a vote on the SkyCity convention centre legislation until after Mr Banks' trial.
PM says Govt still has numbers without Banks
Prime Minister John Key says the Government still has the numbers to comfortably govern following the resignation of Mr Banks as a minister on Wednesday.
The resignation follows that of the leader of National's other support partner, United Future's Peter Dunne, as a minister.
Mr Key says the fact neither is still in the executive doesn't affect National's ability to govern and he isn't contemplating a snap election. He says Mr Banks has indicated he will continue to support National on confidence and supply.
Mr Key says while he doesn't want to prejudge the outcome of the legal action, he is prepared to reinstate Mr Banks if he is found not guilty.
But Labour Party leader David Cunliffe says the Prime Minister will pay politically for his continued support of Mr Banks.
Mr Cunliffe says John Key should not be sanctioning that kind of behaviour, as the public will not stand for it and it will hurt him in the polls. He says Labour would welcome a by-election in Epsom.
Meanwhile, the Prime Minister says Mr Banks' ministerial portfolios will be given to Bill English and Steven Joyce. Mr English will be Minister for Regulatory Affairs and Mr Joyce will be Minister for Small Business. Mr Banks' associate minister responsibilities will revert to the portfolio ministers.
Party president supportive
ACT Party president John Boscawen says John Banks has his support as its leader, as well as the party's backing, and deserves to continue as ACT leader.
"Of course he can stay on as leader, he's been found guilty of nothing. I support him as the ACT leader, I support him as the MP for Epsom as does our board. It's very, very, important that we support him and it's very important that the ACT Party retain the seat of Epsom at next year's general election."
However, Mr Boscawen admits the affair does not help the ACT brand.