The hearing will be held tomorrow morning.
TVNZ's criteria mean parties need to be polling at 3 per cent or have a seat in Parliament. Advance New Zealand, despite polling about 1 per cent, will be included as its co-leader Jami-Lee Ross is in Parliament after being cast out from the National Party.
TVNZ recently relaxed these so the Māori Party could be included after admitting its criteria didn't adequately consider parties who are only contending Māori electorate seats which impact the make-up of Parliament.
Baker said the 3 per cent threshold was "a huge hurdle" for smaller parties "lacking corporate or taxpayer funding".
The most recent 1 News Colmar Brunton poll put the New Conservatives on 1 per cent.
"It's made so much harder by the media failing to do its duty to fairly and reasonably provide information about candidates, parties, and policies so the public can make informed decisions."
Baker then took aim at New Zealand's public and privately-owned media outlets.
"Suppression is not just by police and jackboots. Suppression of political speech, middle New Zealanders, and the disadvantaged, is just as effective by exclusion," Baker said.
"In addition to our publicly-owned media playing this despicable game, there's privately-owned media, like Stuff, actively ignoring and distorting information about voters' options.
"The best message in the world is pointless if no one is allowed to hear it."
Baker said the Herald's 24-page Election Special, which features policy breakdowns and analysis, gave his party "just a few centimetres".
The Herald chose to highlight parties which had been in Parliament for its main policy features. Today's Election Special featured a piece on other smaller parties, including the New Conservative Party.
Baker was also interviewed for the Herald's Leaders Unplugged series which ran at the start of the campaign period.
The Opportunities Party has also previously expressed its frustration at not being included in TVNZ's Multi-Party debate with its leader calling its rules "bat****".