A political commentator believes the alleged Labour Party sexual assault incident is a blow to Jacinda Ardern's brand.

The staffer at the centre of the saga has resigned following allegations of bullying and sexual assault, but he denies the accusations.

Matthew Hooton told Mike Hosking Ardern's persona of being an open, transparent and kind Prime Minister has been tarnished.

Hooton says this goes straight to the heart of the Prime Minister’s brand.

“She is meant to be an open, transparent, kind and huggy type Prime Minister.

"But it has turned out she is prepared to say things to the media which are not true to protect her own circle from serious, criminal allegations.

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