Parliament's Speaker Gerry Brownlee says ACT leader David Seymour has apologised for attempting to drive a Land Rover up Parliament's steps.
Seymour will not be punished for it in Parliament, but Brownlee said whether police lay charges is up to them.
The ACT leader made the attempt on Monday as part of a fundraising drive.
But he was stopped by a security officer who said he had not sought permission from the speaker.
Gerry Brownlee said he had expressed his strong displeasure, but there were no rules that would allow it to be sent to the privileges committee.
"And my concern at his belief that MPs should be able to do what he did as a right. They do not."
He said Seymour apologised by sending him a letter, asking Brownlee to "please accept my apologies for any offence this may have caused".
He commended the security officer.
"His long experience in the role will have given him the necessary judgement to deal with a difficult situation. I doubt he would have ever expected to have to tell a member of the House not to drive a vehicle on the slopes of the building, particularly as it was a repeat of a 2003 event and in light of the enhanced security arrangements that Parliament has since put in place.
"The question of possible prosecution - as was the case in 2003 - is a matter for the police and not the speaker."
Labour's leader Chris Hipkins questioned whether the speaker had advised Seymour that permissions had not been granted for driving the vehicle up the steps.
"David Seymour's comments to the media at the time was that he understood that you had given permission. If it's clear that you hadn't given permission that in itself is a material piece of information."
Brownlee said the event's organisers had asked if they could re-enact a 1948 occurrence where a Land Rover was driven up the steps, but he could not find any reference to that event.
"They were told they could come and have a photograph taken in front of the steps, but most definitely not drive the vehicle up."
He said he would consider the points Hipkins had raised.
Te Pāti Māori's co-leader Debbie Ngarewa-Packer raised questions around danger to the pou on the forecourt at the time.
Brownlee said Parliamentary Service could consider a ban on all vehicles driving onto the forecourt, but in his view that would be an overreach that would affect the openness of Parliament.
Ngarewa-Packer suggested it was a matter of double standards for Seymour compared the hīkoi protest last year.
Brownlee said the protest organisers had been true to their word, and in other protests the organisers had been asked not to mount the steps, but said he was "conscious of the contradiction you have pointed out".
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