Patrick Gower says the disproportionate levels of arrests and prosecutions Māori face for using cannabis is "a form of racism".
As Newshub's National Correspondent, Gower has spent the last two years researching the drug as part of his On Weed documentary series, of which the latest episode aired on Monday night.
He said the figures for Māori arrests and prosecutions are "crazy".
"One thing that's really stood out for me after two years is the impact on Māori and young Māori," Gower said on The Project.
"The arrests, the prosecutions are just so out of whack with the way they should be, and in fact I've started to look at it as a form of racism."
According to a report by the Prime Minister's chief science adviser Juliet Gerrard released in July, Māori are three-times more likely to be arrested and convicted of a cannabis-related crime than non-Māori.
"Coupled with being 10 times more likely to get a conviction if you’re male. Māori men in particular are disproportionately impacted by the illegal status of cannabis," the report said.
Racial biases also could also mean that the discretion afforded to police may privilege non-Māori and disadvantage Māori.
"Though police have discretion to take a health-oriented approach rather than prosecuting those using cannabis, inherent biases in police discretion implied by the disproportionate arrests and convictions for cannabis possession for Māori suggest that this law change may not address social inequities as much as legalising cannabis could," the report said.
"While systemic racism persists in our justice system, the current cannabis laws will continue to disproportionately affect Māori and fuel social disparities."
In the upcoming election, New Zealanders will vote on whether recreational cannabis should be legalised.
Gower said a majority 'yes' vote in the referendum could help lower the levels of arrests and prosecutions for Māori.
"I think it could be a game-changer in terms of that whole issue with Māori and the justice system if people voted to take it out of it."
Watch Patrick Gower on The Project above.