Did you know that Parliament could imprison you for saying that Trevor Mallard is biased in favour of Jacinda Ardern over Simon Bridges? But it (almost certainly) won't.

Wednesday’s flare-up in Parliament, which saw the Speaker ordering both National’s leader and Leader of the House out of the chamber while most of their party colleagues (eventually) followed in solidarity, was either the culmination of longstanding unhappiness with the Speaker’s behaviour, a stunt to distract from internal National Party woes, or a bit of both. Your interpretation of what happened probably says more about your political preferences than anything else.

However, it does focus attention on the rather peculiar role that the Speaker plays in running Parliament, and the rules that protect that office. Simon Bridges and Gerry Brownlee got given their marching orders for implying that Trevor Mallard was acting as Speaker in a way that protected the Prime Minister, Jacinda Ardern, from having to answer tough questions.

That’s a parliamentary no-no, because accusing the Speaker of behaving in a biased fashion undermines the necessary authority of the office. After all, the Speaker has the unenviable job of keeping some semblance of rule-based order amongst 119 other individuals divided into rival political parties who all want to impose their view of how the country should be run.

That’s impossible to do if she or he can be openly denounced as favouring one side over the other. It’s the same basic logic that penalises a sports player who abuses a referee, or a calls him a thief. Even if the player believes this, they can’t come out and say it because without general respect for the referee’s calls the game simply cannot be played.

For that reason, Parliament may treat “reflections against the Speaker” as being a “contempt”; that is, an offence against Parliament itself which it can punish. In 2015, the Privileges Committee (which decides on whether there’s been an alleged contempt of Parliament) summed matters up like this:

“Reflections against the Speaker or other presiding officers, and in particular any comment that alleges that they have been biased in performing their duties, are among the most serious reflections that can be made about members.The rule that it is a potential contempt to make a serious allegation against the Speaker that reflects on his or her impartiality derives from the longstanding practice and tradition of the House of Commons. The rule serves to protect the reputation of the office of Speaker and the institution of Parliament.”

What is perhaps less understood, however, is that Parliament’s power to punish such contempt does not just apply to MPs, or even to events that take place in Parliament itself. It covers anyone who acts in such a way anywhere, as long as their action has the potential to interfere with Parliament’s operations.

So, for example, consider political editor Audrey Young’s published account of Thursday’s events in the Herald: “Parliament’s Speaker, Trevor Mallard, has an inbuilt bias against National Party leader Simon Bridges and a soft spot for Prime Minister Jacinda Ardern.” Such a public accusation of overt favouritism on the part of the Speaker likely could be punished as a contempt, if Parliament wanted to do so.

It has happened before. Back in 1967, a newspaper was censured for contempt after accusing the Speaker of racial bias. And in 2007 the former MP Matt Robson was required to recant and apologise after accusing Peter Dunne in an on-line newsletter of “faithfully deliver[ing] his vote” for liquor and tobacco interests.

And it doesn’t even matter if Young’s claim is true. Because the harm lies in making the allegation itself, not in its accuracy. Even an evidence-based accusation of bias still is a potential contempt.

Does this mean that Young – as well as other journalists, tweeters or bloggers who may say similar things – need to worry about getting a summons before the Privileges Committee? Probably not. For while Parliament could treat such words as a contempt, it doesn’t have to. If it wants to let the matter pass, it can.

In its 2015 report restating Parliament’s powers, the Privileges Committee accepted that it cannot be too precious about what gets said about its members, even its Speaker:

“It is well understood that the House is a place of robust debate and that all members (including the Speaker and other presiding officers) can expect public comment and criticism if their performance warrants it.”

That’s because the MPs on the Committee are politicians and understand that the optics of hauling the political editor of New Zealand’s largest newspaper before them to account for daring to suggest the Speaker prefers his party’s leader over her opponent are none too flash. In fact, it probably would be the quickest way to generate an outcry for Parliament’s contempt powers to be radically curbed.

The ultimate safeguard on Parliament’s use of it power to punish contempt, therefore, lies in MP’s political sense and their assessment of what the public will tolerate. So long as you think you can rely on that, then you can say whatever you want to about the actions of the Speaker or any other MP.