A tweak in the approach to regulating legal highs could provide a glimmer of hope for campaigners demanding a more liberal approach to Britain's drug laws.
Liberal Democrat Home Office minister Norman Baker announced the launch of a review into legal highs today, as the government tries to get a handle on an industry which can alter the chemical compositions of substances faster than it can pass legislation banning them.
And smuggled in there – left unspoken – there was a potentially revolutionary development.
Baker will be taking evidence from several countries' approaches, including the US, where broad families of synthetic drugs are outlawed, and Ireland, where there is a general law banning dangerous psychoactive substances.
But he is particularly interested in the system used in New Zealand, where anyone producing a drug for recreational use is required to obtain a licence, that puts the onus on the manufacturer to prove the substance's safety.
It's a subtle shift, but a vital one. It would set an explicit legal precedent unheard of in Britain since the war on drugs began: that a harmless drug should not be banned.
Any such system would embrace the notion of evidence-based drug policy, where legislation would be dependent on the harm of a substance.
That is very far away from the approach of the Home Office in recent years, where the advice of the Advisory Council on the Misuse of Drugs is frequently disregarded by Home Office ministers where it proves too liberal.
Professor David Nutt, the former head of the council, was sacked by then-home secretary Alan Johnson after he pointed out that, statistically, taking ecstasy was no more dangerous than riding a horse.
The creation of a licensing system which allowed the sale of psychoactive substances which present no risk to health would be a huge change to drug policy.
It would encourage an industry to take advantage of the freedom offered to substances which demonstrably cause no damage to the body.
That would be a significant shift from producers' current approach, which relies on pretending their products are 'plant food', 'research chemicals' or 'unsuitable for human consumption'.
But it would also offer those who want a rational, evidence-based approach to drugs policy a foot in the door - a legal framework from which a larger argument can be made about how to regulate recreational substances.
The potential for a more liberal regulatory system is the latest sign that Baker intends to try to secure enlightened changes at the Home Office.
The Lib Dem is keeping his cards close to his chest as he navigates the difficult political reality of operating in the department, which has not seen a liberal (with a small 'l') occupy a position of power for decades.
Even his comments on today's review offer few signs of how potentially liberal its outcome could be.
"The coalition government is determined to clamp down on the reckless trade in so-called 'legal highs', which has tragically already claimed the lives of far too many young people in our country," he said.
"Despite being marketed as legal alternatives to banned drugs, users cannot be sure of what they contain and the impact they will have on their health. Nor can they even be sure that they are legal.
"Our review will consider how current legislation can be better tailored to enable the police and law enforcement officers to combat this dangerous trade and ensure those involved in breaking the law are brought to justice."
Unfortunately but predictably, Labour's response has been of the stock authoritarian variety. Shadow crime minister Diana Johnson berated the Home Office for not acting quicker and demanded the prosecutions of shops selling the drugs.
"If this Tory-led government was serious about helping to close down these shops they'd back Labour's amendment," she said.
Of course, if Labour was serious about preventing harm to young people, it would adopt a more liberal, rational approach to the legal high industry.
The makers of legal highs can subtly alter the chemical make-up of a drug while retaining its effect. They are much faster and nimbler than statutory legislation.
The number of cannabinoids, stimulant powders and other psychoactive substances in circulation has tripled in four years, with a new legal high reaching the market every week. There are about 700 websites alone selling the products.
There is little point trying to be ever more authoritarian on these substances. It's like watching Tom trying to catch Jerry. It may look as if something is being done, but he'll never manage it.
If we are really worried about our children, and not the reaction of the tabloid press, we would institute a regulatory structure that makes it clear that only safe substances would be on sale in shops.
There's no guarantee the New Zealand model will win the day. There will be plenty of opposition from the Home Office before it publishes its conclusions in the spring. But the fact it is even being countenanced suggests Baker is making significant inroads at the Home Office.