But a much more important case of political slipperiness this week was Judith Collins' reaction to last week's Herald on Sunday story that police in Counties Manukau had downgraded several hundred burglary offences to "incidents", presumably to make crime statistics look better.
Except it wasn't news to Collins, who was Police Minister at the time — she had been informed that there was statistical skulduggery afoot but forgot to tell anyone.
Her response to this very serious accusation was to accuse Labour's Jacinda Ardern of playing politics.
The problem is not Ardern. The problem is that police fiddled with crime statistics. Knowing it occurred in this case casts doubt on the integrity of any and all reports of improved crime statistics.
Who benefited from this fudging? Certainly not you and me with our back-of-the-mind concerns about our chances of being burgled. Possibly the police and maybe even the minister, both of whose reputations were enhanced by an apparent drop in crime under their watch.
If our MPs have one firm principle to which they adhere — and you'll be relieved to know there is at least one — it is a refusal to admit they were wrong. It's a truism that we learn from our mistakes, but first we have to admit them.
Collins has had many learning opportunities this year. Call me a dewy-eyed optimist but I sometimes imagine a world run by people who acknowledge their errors, apologise for them and demonstrate their sincerity by doing something to fix them.
I find it a consolation every time I pick up a newspaper and steel myself to encounter another sorry catalogue of ineptitude and moral amnesia.
It seems the Labour Party has quietly adopted a policy that te reo Maori will be taught in all schools.
Well, even if it is official Labour Party policy, I am still in favour of it.
I argued for universal teaching of te reo in this column a long time ago. To summarise the reasons: learning a second language is good for brains at any age; most of the world speaks English as a first or second language so the historically vaunted commercial reasons for learning Japanese or Mandarin no longer hold true; bilingualism is good for relations between Pakeha and Maori; language is not only a repository of culture, it is also the safest place to keep it and ensure its survival; finally, if te reo Maori is not taught in New Zealand, where will it be taught?
However, Labour is not keen to publicise the policy. How can you have a policy you're not prepared to stand up and argue for or that you don't believe you can convincingly explain to people who might not care for it at first sniff?