A Broadcasting Standards Authority has upheld a complaint about the unbalanced airing of "the reactionary views of an unqualified right wing individual" by TVNZ's Breakfast show.
A viewer lodged the complaint after an interview last December of Sensible Sentencing Trust's Garth McVicar.
During the discussion, Mr McVicar criticised the leniency of a 21-month prison sentence given to a gun collector convicted of illegally selling a large gun collection, saying the judge had "got it wrong".
Complainant Roger Brooking said: "No attempt was made to present the other side of the argument on sentencing and law and order issues."
The interview enabled Mr McVicar to "repeatedly air his right wing populist views about law and order, generally criticise judges for being too lenient on criminals and expound his belief this fails to send a message of deterrence to other criminals in the community".
Mr Brooking said a lawyer or a criminologist should also have been interviewed and it was inappropriate for the broadcaster to present "the reactionary views of an unqualified right wing individual as if he was the oracle of sentencing law".
He also said the presenters expressed sympathy for Mr McVicar's views.
TVNZ refused to uphold his initial complaint, saying it had already balanced the story across its other shows.
However, in its decision, the authority said none of the items the broadcaster referred to offered any balance to the McVicar interview.
It found TVNZ breached the requirement for balance by providing only one viewpoint when discussing a controversial issue of public importance.
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