The debate around the cannabis referendum are heating up as the country gets closer to election day. 

A new ad from the Say Nope to Dope campaign has raised eyebrows, after suggesting drug driving will be legal if the public votes in favour of legalisation.

In the ad, a mum tells her kids that they will start driving once their Dad has finished his joint. 

Spokesman Aaron Ironside told Heather du Plessis-Allan that the ad is suggesting that the use of cannabis will go up in adults. 

"It's not at all beyond the pale of expectation that people could smoke and go for a drive because we know they already do."

He says statistics from Washington DC suggest one in five drivers there will be found with cannabis in their system. 

Ironside says the group does not deny that driving after taking drugs will remain illegal, but their use will increase after legalisation. 

He does not believe the ad creates a false impression of what is legal. 

"We've painted a couple of scenarios in our ads that simply state this is the change to every day life when families start having cannabis more and more commonplace."

Another ad they've released has a child accidentally taking a cannabis brownie. 

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