Politicians often get a bad wrap, even when they do not deserve it. In that regard, they are one of society's safety-valves. They are always good to sound off against.

Of course, there are times when politicians' actions are so egregious to deserve all the criticism they receive. This week's disgusting news from Australia about the comments of a male Australian Senator about the private life of a female colleague, for which he has steadfastly refused to apologise, would be near the top of the list, and absolutely nothing can be said in his defence.

But there are other occasions when it is the sheer stupidity or trivial vacuity of the MPs' comments that deserve the public scorn. The mini-furore that has erupted over Air New Zealand's decision to change the composition of the hamburgers it serves to Business Class passengers on long-haul flights is a great example. A veritable chorus of outrage has exploded around the House about how appalling this change is, and what a blow it strikes against our meat industry. MPs seem to be falling over each other to appear the most offended.

What poppycock! This is hardly the issue of the day, nor is it likely to bring the New Zealand meat industry to anywhere near its knees. Yet it is a good opportunity for MPs the public would otherwise hear nothing of to set off their outrage button, and presumably feel a sense of self-satisfaction at their pontifications. And Air New Zealand will continue to serve their menu, and their passengers will either take it or leave it, without the slightest consideration of the MPs' ramblings. The notion that an airline's menu should be set by Parliament is simply farcical.

And then there is the "never let the facts get in the way" approach. By way of a disclaimer, I am no admirer of New Zealand First, its policies, or its at best barely marginally competent MPs, but the uproar over the Inquiry into the appointment of the new Deputy Police Commissioner borders on the ignorant and the absurd.

For the record, the comments of the new Deputy Police Commissioner at the time of the trials of former Police Officers on sexual assault charges were unacceptable, and despite his apology now, raise major questions about the way his appointment was made and the current level of sensitivity within the Police when it comes to dealing with such issues. So the proposal to have an Inquiry into the circumstances and process of the appointment has merit.

The allegations that such an Inquiry will not be unbiased because the Minister of Internal Affairs, who will oversee it, is a senior New Zealand First MP, and the Deputy Commissioner sought a New Zealand First candidate nomination at one stage, are ridiculous. They overlook the simple fact that the Inquiries Act, passed as recently as 2013, makes the Minister of Internal Affairs the responsible Minister for all such Inquiries. Of course, the Minister does not conduct the Inquiries personally, but is responsible, subject to Cabinet approval, for selecting those who will conduct the Inquiry and securing the resources they will need to do so.

The Inquiries Act was passed when National was in power, and many of the MPs now leaping up and down alleging bias, voted for it. Selective memory is a possible explanation for the about-turn - a more likely one is the obverse of the so-called Maharey principle: say one thing in Opposition, but do something else in Government, and just hope not too many people will notice.

The current Government made many rash promises while in Opposition, more to staunch the bleeding of Labour votes than with any real expectation of ever having to implement them. Now they are struggling to make their impossible dreams work. One would have thought their experience would have been a salutary lesson to the current Opposition of how not to get tied up in credibility knots. But railing against airline menu changes and Inquiries properly constituted under legislation they promoted in Government suggests not.

Being in Opposition - especially unexpectedly after a long spell in Government - is understandably soul-destroying, but it is no licence for the stupidity it often seems to descend to.