New Zealand First leader Winston Peters wants answers from the police about why they closed the investigation into Clutha-Southland MP Todd Barclay recording his staff.
"Why, when they had a clear allegation of a potential crime, that is a breach of privacy which is a serious offence, did they stop the inquiry?" Mr Peters asked.
He believes there was political meddling involved.
"The details are so simple. Someone illegally tapes the communications of others when he wasn't there". He said that Mr Barclay should be held to account. "The fact that his lawyer said 'don't see the police' tells me frankly he's guilty as sin. Now Mr Barclay can sue me can't he? But I bet he won't."
But Prime Minister Bill English doesn't think the recording scandal has damaged his reputation or that of the National Party, as pressure continues to mount over his role in the situation.
"I don't think it's damaging. It's important that these issues are dealt with but in the context of a Government that is dealing with the issues that matter, a united Government, cohesive, we deal with these sorts of issues even if they're difficult and even if they're personal."
Mr Barclay announced on Wednesday he will not stand again in his Clutha-Southland seat, after persistently denying doing anything wrong. On Tuesday he said he hadn't told Prime Minister Bill English he made any recordings during a period when tension in the office was running high.
That was later blown apart when Mr English said he had made a statement to police last year in which he confirmed Mr Barclay had told him that he did make the recordings. Mr Barclay will leave the seat in September.
Labour leader Andrew Little has also called the situation a cover up, and a failure of leadership by Mr English.
"I cannot understate the magnitude of this as a failure of leadership. This is a guy that's been in Parliament 27 years," he said. "This was a cover-up by the National Party, I'm sure there were others involved. They were doing everything they could to conceal this from the public."
Police closed the investigation and never laid charges. Mr Little says police now need to be left to reassess the claims.
A win for Winston?
Mr Peters said his party will capitalise on National's woes in Clutha-Southland at the election.
"We're going to get some serious backing down there, because it's been building up for a long time. It shows up in our meetings."
He stopped short of saying his party would win the seat off National, like it did in Northland in 2015.
The scandal is the latest in a number of problems for National. It follows news of a funding blunder within the district health boards, and revelations Transport Minister Simon Bridges tried to block an official information request.
Massey University political commentator Professor Richard Shaw says after three terms in Government, parties can drop the ball. "Often after that length of time Governments begin to take things for granted. There might be a sense of entitlement that develops."
Prof Shaw says an ongoing investigation may also take the focus off their election promises.
"It would be a problem for them if they lose momentum because of the distraction that this thing could become."
NZN / Newshub.