Napier mayor Bill Dalton has criticised the Government's refusal to ban party pills and other psychoactive substances as "a cop out" and says it is dumping a costly problem on councils.
Associate Minister of Health, Peter Dunne, who pushed through the Psychoactive Substances Act last year, said a ban would not work because drugmakers would simply change the chemical make-up of the drugs to get round the law.
He said the law gives councils strong powers to regulate drug sales and commends Napier as one city that's done just that.
However, Mr Dalton said the council is powerless to shut down one shop, which he said attracts queues of undesirables, terrifying members of the public and other retailers.
The mayor said he has been to the shop personally and "remonstrated" with the owner, who called the police.
The police told the mayor he had to leave.
"There's no way they are going to voluntarily shut their doors," said Mr Dalton.
"Any attempt we make to shut them down via the means suggested by Mr Dunne will be met with legal action because these guys have too much to lose."
Mr Dalton said the Government should implement a blanket ban on all psychoactive substances and products and then exempt those that are covered by existing legislation.
However, it seems the Napier shop has become a useful focus for the police, who have been carrying out vehicle stops in the street to check driver-licence breaches, registration and warrants of fitness, people wanted on warrants and people with outstanding fines.
In a two-hour period on one day in March, police officers issued more than 40 tickets outside the shop and arrested a man who owed more than $40,000 in unpaid fines.
The store's manager refused to comment to Radio New Zealand on Friday.
Hamilton City Council, which has brought in rules limiting drug sales to its central business district, faces a judicial review in court. Other councils have criticised the law as weak and unworkable, saying retailers and councils will have to spend hundreds of thousands of dollars on court actions to get clarification.