She said it was wrong for retailers to try to get rid of any old stock they may have by selling them illegally.
"I had a lady come up to see me [in the Whangarei police station] the other night about her son who is up on burglary charges. She said he was good boy who had a job and was doing well until he started smoking K2 [one of the synthetic cannabis products]," Ms Phillips said.
"She said some retailers were still selling these products. Then I had another tip off [about places still selling them], so we will be checking up on them and if we catch anybody we will be prosecuting them."
Ms Phillips said police would team up with the Northland District Health Board and Whangarei District Council to look at the issue and may well do something similar to the controlled purchasing operations done in relation to selling alcohol and tobacco to underaged customers.
Under the new bill people who commit an offence can be liable on conviction to a term of imprisonment not exceeding three months or a fine not exceeding $500,000, or both.
At yesterday's meeting Councillor Aaron Edwards said he'd prefer the substances to be referred to as legal highs as it was a misnomer to call them synthetic cannabis.
Cr Edwards said that gave the impression that they were synthetic, safer versions of cannabis and would have similar effects, but that wasn't the case.
Ms Phillips said it was gong to be very tough for people to prove that their products were safe before they could become a legal high under the bill.