Sceptics say move to group cannabis containing more than 15% THC with cocaine and ecstasy will be hard to enforce

This article is more than 8 years old

This article is more than 8 years old

The Dutch government has said it will move to classify high-potency cannabis alongside hard drugs such as cocaine and ecstasy, the latest step in the country's ongoing reversal of its liberal policies.

The decision means most of the cannabis now sold in Dutch coffee shops would have to be replaced by milder variants. But sceptics said the move would be difficult to enforce, and that it could simply lead many users to smoke more of the less potent weed.

Possession of cannabis is technically illegal in the Netherlands, but police do not prosecute people for possession of small amounts, and it is sold openly in designated cafes. Growers are routinely prosecuted if caught.

Maxime Verhagen, the economic affairs minister, said cannabis containing more than 15% of its main active chemical, THC, is so much stronger than what was common a generation ago that it should be considered a different drug entirely.

The high potency cannabis has "played a role in increasing public health damage", he said at a press conference in The Hague.

The cabinet has not said when it will begin enforcing the rule.

Jeffrey Parsons, a psychologist at Hunter College in New York, who studies addiction, said the policy may not have the benefits the government is hoping for.

"If it encourages smoking an increased amount of low-concentration THC weed, it is likely to actually cause more harm than good," he said, citing the potential lung damage and cancer-causing effects of extra inhalation.

The Dutch justice ministry said it was up to cafes to regulate their own products and police will seize random samples for testing.

But Gerrit-Jan ten Bloomendal, spokesman for the Platform of Cannabis Businesses in the Netherlands, said implementing the plan would be difficult "if not impossible".

"How are we going to know whether a given batch exceeds 15% THC? For that matter, how would health inspectors know?" he said. He predicted a black market will develop for highly potent cannabis.

The ongoing Dutch crackdown on cannabis is part of a decade-long rethink of liberalism in general that has seen a third of the windows in Amsterdam's red light district closed and led the Netherlands to adopt some of the toughest immigration rules in Europe.

The number of licensed coffee houses has been reduced, and earlier this year the government announced plans to ban tourists from buying cannabis. That has been resisted by the city of Amsterdam, where the cafes selling cannabis are a major tourist draw.