"The Immigration Act 2009 provides that entry permission may not be granted where there is reason to believe there is, or is likely to be, a threat or risk to public order or the public interest.
"Odd Future has been deemed to be a potential threat to public order and the public interest for several reasons, including incidents at past performances in which they have incited violence. In one instance, a police officer was hospitalised following a riot incited by Odd Future,'' the statement read.
That riot? Was caused by cops when they broken up a signing when too many fans showed up. And the injury was a cop falling over and hurting his back. From the sound of them, I wouldn't like Odd Future at all - but as a "threat to public order" goes, that's exceptionally weak, and certainly no grounds to violate their freedom of expression, or that of their New Zealand fans. This ban is simply Muldoonist bullshit.
(I'd suggest Odd Future seek to have the ban judicially reviewed for illegality, but it would take too long, the harm will already have been done, and those who made the decision will not go to jail for BORA violation. Which is one way governments get away with unlawful actions: because they effectively have impunity from any consequences)
As for how to deal with groups like Odd Future, I've said it before and I'll say it again: the answer to speech you don't like is more speech, not less.