Labour's chief whip says the alleged assault of an MP's wife on Saturday is unacceptable, and reignites concerns about the threats MPs and their families face.
A spokesperson for New Zealand First's Shane Jones says he was verbally abused at Auckland Airport and his wife was assaulted, with someone grabbing her shoulder.
Police say they are in the process of obtaining a formal statement from one of the parties involved.
Labour Chief Whip Glenn Bennett said accessibility to politicians in public was a good thing but it should never come with the risk of harm.
He told Morning Report the incident was "unacceptable" and no-one deserved to be in that position.
"I know little of what actually happened, but the sad thing is people feel they have the right to confront people just going about their days and doing their jobs - and also people who aren't even politicians."
Last year an Otago University study looked at harassment of politicians, finding 98 percent of the 54 MPs who took part said they had experienced harassment, ranging from disturbing communication to actual physical violence".
"I'm proud of the fact that New Zealand has a very accessible, relaxed access to politicians.
"The fact that I can go to the supermarket or be at the local cafe and actually have people approach me to talk about issues that matter to them, that is a really good thing. But it's, when it crosses that line, to ... harrassment, aggression, that is not okay, and it has been rising, and it's not acceptable."
Bennett said parliamentary security and police had recently beefed up support for MPs.
Police said on Sunday no injuries were reported as a result of the confrontation.
Shane and Dot Jones have declined to comment to RNZ as the matter is now with police.