"Reporting on the alleged actions of one councillors and the alleged inaction of the HDC had the ability to severely damage the public's confidence in the HDC to operate effectively and in the interests of the public.
"The broadcast clearly approached the story from Campbell's perspective."
In its ruling the BSA ordered MediaWorks Radio Ltd to broadcast its statement during Magic Afternoons with host Sean Plunket on MagicTalk after the midday news, on a date to be approved within the month.
MediaWorks wanted the decision to appear in print only, citing that The Long Lunch was no longer on air, that RadioLive was disestablished late last year and replaced with MagicTalk, and that Nissen was no longer employed by MediaWorks.
But the BSA ruled that the statement must be broadcast on MagicTalk the same day of the week as the original item aired on RadioLIVE, so as to reach the same audience and remedy the potential harm caused.
The statement is to contain a comprehensive summary of the BSA decision and be approved by both HDC and the BSA before broadcast, it said.
The BSA found there was potential for harm to the reputation of the HDC by the Campbell interview, as it was a publicly elected body that relied on the support and confidence of its constituents.
HDC originally laid a complaint with the BSA, citing the interview breached the fairness, balance and accuracy standards of the Radio Code of Broadcasting Practice.
It said councillors and officers were certain to be adversely affected by Campbell's unchallenged allegations of bullying and neither HDC, its officers or councillors, were given opportunity to comment.
It claimed Mediaworks made no reasonable effort to ensure Campbell's allegations were accurate. Listeners were likely to be misinformed without a balanced response from HDC.
Listeners had the right to assume the broadcaster had undertaken some investigation of Cambell's claims before letting him go live on air.
The BSA decision found the broadcast was likely to mislead audiences by giving the impression that HDC had a systemic culture of bullying.
"We have found that the broadcast as a whole was misleading, as a result of the omission of material points of fact.
"Broadcasters have a responsibility to tell important stories in a balanced, accurate and fair way, so that undue harm is not caused to individuals and organisations, or to audiences generally."