A Catholic school in Ponsonby has drawn criticism for erecting a billboard urging people to "say no" in an upcoming referendum on liberalising cannabis law.
In a photo uploaded on Reddit, a sign outside St Paul's College says: "To legalise is to normalise, say NO".
A Reddit user wrote: "Isn't it illegal for a high school to push political opinions on students?"
Other concerned readers have contacted the Herald saying the school shouldn't be pushing a political agenda on its school community.
According to the Ministry of Education's website, boards of trustees can allow billboards on school grounds for "general, not political, advertising" only.
"You must have an agreement in place before the billboard goes up," the website reads.
The ministry says while schools can display material encouraging staff and parents to vote, a state agencies schools must be politically neutral and "can't encourage electors to vote or not vote for specific parties, policies or candidates".
During the upcoming general election, voters will be faced with a referendum on whether or not the recreational use of cannabis should be legal.
Earlier this week the Helen Clark Foundation co-hosted a webinar with the Drug Foundation with the former prime minister herself saying criminalising cannabis is an injustice to thousands of people every year.
Her comments came on the back of a new poll showing a tight race for the September referendum on legalising cannabis for recreational use, with 48 per cent support in favour and 43 per cent opposed.
"Let's get real here. This is a widely-used recreational drug that is less harmful to individual health than tobacco and alcohol," Clark told the webinar.
"Most Kiwis will use it in their lifetime. They know their teeth don't fall out and their hair doesn't go green. Most people don't use it very often, unlike alcohol."
The proposed legislation includes an age limit of 20, redistribution of tax into harm reduction, health and education programmes, a ban on all marketing and advertising of cannabis products, and a limit on potency.