This was the third consecutive Friday the group has held public protests, with the first outside Whangarei Courthouse and the second in Mair Park.
The group has vowed it will continue the protests until cannabis laws are reformed so that the drug is legalised.
The spokeswoman said the group wanted cannabis to be legalised for personal use for people aged over 18. She said members were fully aware that they could be arrested.
She said several states in the United States and Canada had legalised the drug for personal use "and it's just a matter of time before it happens here."
Whangarei Police Sergeant John Larkin said the law is that cannabis is illegal and people who smoked or possessed it in public would be arrested.