Labour is accusing Television New Zealand of instructing staff on its Fair Go programme to avoid stories that might upset advertisers.
At a Commerce Committee hearing at Parliament, TV One head Jeff Latch said he told staff that any story should be balanced and there was no suggestion that they should avoid stories about businesses that advertise on TVNZ.
Mr Latch said he was talking about how to make the programme more successful.
But Labour says the warning that Fair Go operates in a commercial environment and staff need to take care, could undermine the show's integrity.
Former presenter Brian Edwards also says it sounds more like an instruction to journalists.