Why did the Labour Party get it so wrong? How does an organisation committed to social justice, its ranks full of feminists, not know how to do the right thing when presented with allegations of sexual abuse by one of its own?
Perhaps we don't know all the facts. In matters like this it would be unusual if we did. But would that justify it? It's hard to see why.
The party was told, repeatedly and by several complainants, about sexual abuse. Yet somehow, say the people involved, they didn't hear it.
What is it that allows organisations to make decisions the rest of us can easily see are wrong? Why are some of those things not only wrong from a moral point of view, but against even the organisation's own best interests?
In psychology, they talk about cognitive biases: the ability to draw the wrong conclusions from a set of information, because ideas and values already in our heads shape the way we think about that information.
We're scared of the dark. We see a person standing on the path up ahead, when it's just the way the shapes and shadows of the shrubbery fall. This type of cognitive bias is mostly not useful now, but it used to be: it kept people alert to the danger of attack from a wild animal. Natural selection kept this instinct alive for thousands of years.
In social relations, that cognitive bias often shows up in reverse. We tend not to see danger. We take risks that don't feel like risks, because we've taken them before. Politicians and their officials come in contact all the time with people who have a grievance that isn't as important as they think it is. It doesn't feel risky to shut them down because they do it all the time.
Is that what happened in the Labour Party, or was it more complicated than that? Was it the kind of misunderstanding known as confirmation bias? This is where you tend to see only the bits of evidence that confirm what you already believe.
Perhaps the officials believed the person complained about was a valuable, upstanding party worker. That might make them inclined to assume the problem was smaller than it really was.
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It's easy to scoff at that, but confirmation bias is really common. It's the way almost everyone actively engaged in politics thinks: what their party does is likely to be right and their mistakes are not as big as other parties wants us to believe.
The rest of us are also easily gulled by our own biases. People with views on climate change, the quality of the All Blacks, the best way to roast potatoes, the best candidates standing for their local council right now, are all likely to suffer from confirmation bias.
Or was it what might be called authority bias? Society is riddled with this too. In old-fashioned family structures, father is right. In "traditional" schools, the teacher is right. In the workplace, the boss is right.
Courts tend to operate on the assumption that the police are right. Officially, it's not true, but in practice it plainly is. Authority bias helps explain the terrible injustices done to Teina Pora, Arthur Allan Thomas and many others: despite what should have been an obvious lack of compelling evidence and illogical analysis, juries and judges repeatedly believed the police in both those cases. Why? For no better reason, it seems, than that they were the police.
One of the unifying features of authority bias everywhere is that its truest believers are the people with the authority. Whether it's because of their "superior" education, the experience from which they have learned so much or just years of unassailable confidence, they know they're right.
If the party boss says it's like this, it can take both independent thinking and courage to disagree.
Then there's organisation-protection bias. If you're in a political party and it's drummed into you that the priority is always, always, to build the credibility of the party so you can win the next election, your instinct, which you trust, is to bury problems.
It's not only politics where this happens. This is the way large companies behave too. Those HR departments might work hard to win your loyalty with IT training and birthday bunfights, but their core job is to ensure any problems that arise through staff issues do not undermine the company.
When an employee complains it's likely the focus will be, not on addressing the cause of the complaint, but on shutting it down. Often that means removing the complainant, with the minimum possible payoff and a non-disclosure agreement to keeps things tidy.
In politics, this gets ramped up because they're on a wartime footing. The other side is the enemy. The first and last thing they say when anything goes wrong is, if this gets out the opposition will use it to try to destroy us. Which is likely to be true. It's not paranoia if they really are coming to get you.
In politics, particularly on the left, the social-democrat side, there's another factor. They're on the side of the angels. They believe they're making the world a better place. This is not a criticism: it would be nice to think everyone in politics is there to increase the common good.
But believing you're the good guys has a downside. It tempts you to attach a moral imperative to everything you do, even when it's undeserved. The means, perhaps, justify the end. The bigger picture is more important than your little problem. You have to suck this up for the good of the party. We can't be the bad guys, because, remember, we're the good guys.
It's a corrosive way of thinking, and those who indulge in it are the most likely of all of us to get things wrong.
When people do bad things, they usually tell themselves they're entitled to do it, one way or another. When people in authority are called on to deal with the consequences, the place to start is to recognise they may not be seeing the problem right.
When Jacinda Ardern took charge, she talked about wanting to lead a kinder, gentler country. She hoped we would evolve better ways of conducting ourselves in the rough and tumble of politics and wider social life.
Making that happen isn't about expunging a few bad people from the corridors of power. It's systemic, psychological and political, and it requires the evolution of a different culture, not just in politics but everywhere. We're all in this, and National shouldn't be smug about it; there's no evidence they're any better at handling these types of complaints.
Kindness, and the decency to handle allegations of wrongdoing with understanding, compassion and fairness, have not been killed off in this scandal. They're still goals worth pursuing, now more than ever.