The formerly secret Spencer Trust may have paid the $40,000 court costs awarded against Winston Peters in his unsuccessful Tauranga electoral petition against National MP Bob Clarkson.
Such a payment would have been perfectly legal but it would be at odds with what the privileges committee has previously been told by Mr Peters, the New Zealand First leader, and his lawyer Brian Henry.
And a declaration to Parliament may have been required.
The Serious Fraud Office is conducting an investigation into donations to the Spencer Trust for New Zealand First and is thought to have submitted evidence to the privileges committee this week.
But Mr Peters launched a stinging attack on the integrity of the SFO yesterday. Attorney-General Michael Cullen, the Minister in Charge of the SFO and a member of the committee, refused to express confidence in director Grant Liddell.
The issue of the court costs arose during questioning of Mr Henry by the privileges committee as it examines when Mr Peters knew about the payment by billionaire Owen Glenn of $100,000 towards the legal fees for his petition.
Mr Henry told the privileges committee on August 18 that he personally was paid the money and that Mr Peters had not known about it until that evening.
Mr Peters raised doubts about that claim the same night when he appeared before the committee and two days later said that after a check of his records he could say he had reimbursed Mr Henry the money.
Mr Peters appeared before the committee for a fourth time yesterday to respond to private evidence provided by the Serious Fraud Office. Mr Peters' evidence was heard in private because the SFO evidence was submitted in private but it is all expected to be made public when the committee tables its report next week.
Mr Peters has stood down as Foreign Minister while the SFO investigation is conducted though he remains a minister without portfolio.
It has become apparent that the trust has channelled donations to New Zealand First that it should have declared to the Electoral Commission.
The $40,000 costs were awarded against Mr Peters on March 9, 2006, and Mr Henry's cheque was received by Mr Clarkson's lawyer, Peter Kiely, on April 5.
The Spencer Trust has said it paid $87,648 of NZ First's bills in 2006 - bills the party itself has no record of.
Spencer Trust trustee Grant Currie would neither confirm nor deny that it paid money to Brian Henry.
Mr Currie said the trust made payments to the "benefit of" New Zealand First.
Mr Peters yesterday attacked the motives of the SFO which has had a reprieve from a planned merger into the police while it investigates New Zealand First.
He produced an anonymous letter sent from an SFO staff member to New Zealand First MP Ron Mark condemning his support for the abolition of the office.
The SFO inquiry into New Zealand First was launched a week later.
Mr Peters said the SFO had been shown up during the Winebox inquiry to be totally incompetent "and they are back engaged in what is a totally political action designed to secure their survival". He believed the SFO had acted outside its powers and with malice "and I'll set out to prove it".
He said the SFO had found nothing on his party and had "sneaked into the back of this committee to try to keep their case going".
After the committee rose, Dr Cullen said that at a regular meeting with Mr Liddell on Monday he would be discussing the sending of an anonymous letter by an SFO staffer to Mr Mark.
"The SFO is able to make submissions to the [law and order] select committee but I don't think anonymous letters of a slightly threatening nature are appropriate to come from members of the Serious Fraud Office."
He would not be drawn into comment on anything to do with the privileges committee.
Asked if he had confidence in the director, he replied: "At this point I prefer not to comment on that either."
Mr Liddell said he had decided to start the investigation after careful consideration of all relevant material.
"I reject claims that there is any impropriety, improper purpose or bias in my decision."
On the issue of the letter, he said he had not seen it. "Nonetheless, I take seriously that a staff member may have written an unauthorised communication, and I will be taking immediate action to determine whether it may have come from an SFO staff member."
Meanwhile Mr Glenn on September 17 sent a letter to the committee effectively standing by everything he had told it previously. Mr Peters tabled a response saying Mr Glenn had 27 conflicting statements "which begs the question - why would any fair hearing find Mr Glenn's evidence more compelling than mine?"
However, Mr Peters did not attack the most damning evidence: records of a phone call between Mr Glenn and Mr Peters followed immediately by an email to Mr Glenn from Mr Henry referring to his conversation with Mr Peters and providing bank details.
WHAT IS LIKELY TO HAPPEN NEXT
* Parts of the committee's draft that criticise Winston Peters and Brian Henry will be sent to them for comment over the weekend.
* The committee meets again on Monday at 4.30pm to consider the Peters-Henry response and approve a final report.
* Privileges committee report tabled and debated Tuesday afternoon.
- Patrick Gower