It is hard to think of a subject more damaging to this Government than an accusation of sexual assault against someone who works on the Labour leader's staff.
No party professes more care for women, more determination to advance status and rights and more sensitivity on questions of sexual abuse. How is it possible, many of the public will be wondering, for anyone working in this party's supposed culture to behave in any way that could give rise to allegations of sexual misconduct?
This is not the first time the party has received such an allegation, of course. The first arose from a summer camp, a rather different environment than parliamentary offices with a wider range of party members present. But that allegation too was handled badly.
An internal report into that incident, still under wraps, prompted Jacinda Ardern to say
the party needed to deal with such issues in a better way.
It is all the more surprising, then, that a second case has been mishandled. Seven people had made complaints against the parliamentary staffer, a party member, alleging bullying, intimidation and sexual assault. Labour's president Nigel Haworth, who has resigned this week, says he was not aware they included sexual assault.
He set up another internal inquiry which did not consider sexual assault and that resulted in no action being taken. When the complainants were informed of this some of them went to media.
Ardern says that was the first she knew of sexual allegations. She asked someone on her staff to check whether sexual harassment or physical assault had been alleged and she was told no.
Now that she has read material made public she knows otherwise. Why did she not make more effort to find out much sooner? Prime Ministers are extremely busy, they need to keep abreast of most matters of government and depend on trusted staff and party officials to deal with internal issues.
But Prime Ministers also set the culture and expectations of their office. This Prime Minister could have been expected to be especially alert to any issue of this nature.
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The National Party naturally is asking these questions of her. This embarrassment is a gift to them. Ardern is the Government's strongest political card and this is a subject close to her heart. National's deputy leader, Paula Bennett, is leading its charge on this one.
It is not so long since National held an inquiry into its own treatment of women at Parliament arising from allegations against the now independent MP, Jami-Lee Ross, which did National no apparent harm in polls. It will be surprising if Labour is as fortunate.
The complainants, some of them Labour volunteers, are deeply disappointed at the way they have been treated. It creates an impression this is a government that doesn't match its worthy sentiments. From the top down on this one, Labour has been weak.