‘But how exactly is it illegal?” Sometimes, students ask you very smart questions. This week one of my undergrads at GCU was reading about the exertions of Peter Krykant to establish a safe injecting facility in Glasgow city centre. They’d read about what he was doing in the city – trying to provide a safer and supervised venue for drug users, with naxolone on hand in case of overdoses and sterilised needles available to arrest the spread of HIV. They’d read the news reports and the Misuse of Drugs Act. But what they couldn’t immediately fathom was: which part of Mr Krykant’s activities are potentially illegal?

It is often simply asserted that Krykant’s mobile consumption room must be unlawful, but having dug through the legislation in a little more detail this week – I’m now much less convinced this is necessarily so. Last year, SNP MP Tommy Sheppard asked the Lord Advocate about the legal basis for criminalising drug consumption rooms. James Wolffe’s answer sounded insuperable. It is worth quoting in full:

“Section 4 is supplying and being ­concerned in the supply of drugs. Section 5 is possession and possession with intent to supply. Section 8 is a provision directed specifically at the manager or occupier of premises that are used for certain drug consumption activities, so potentially the board, the council or staff. Section 9 is the consumption of opium and section 9A is the supply of articles for administering or preparing drugs. There are also ­potential ­issues under the Smoking, Health and Social Care (Scotland) Act 2005 and the Psychoactive Substances Act, and there are potentially crimes of culpable and reckless conduct and culpable homicide in the common law, so a wide range of statutory offences and, potentially, common law ­offences, could be committed by users, staff and those operating the facility.”

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This sounds like a formidable array of legal objections, but when you dig into the detail, the case for the prosecution ­becomes much less convincing. Drug ­users themselves would certainly be committing criminal offences of possession. That’s crystal clear. But what about activists like ­Krykant? Where precisely does their behaviour fall under the legislation? Digging into the detail this week, I’m now much less convinced that the issue is as black and white as the Lord Advocate’s answer seems to suggest.

The criminal law imposes no general duty on members of the public to intervene if somebody else commits a crime. It doesn’t criminalise bystanders who watch another person committing a crime, or for failing to call 999. And injecting drugs is not a crime.

Yes, it is an offence for an occupier or manager of “premises” to permit the “production or supply” of drugs there – but there is no evidence Krykant’s ­mobile unit is doing either of these things. Yes, there are particular prohibitions on the preparation of opium or cannabis for smoking – but as far as I’m aware, neither of these things is happening in the ­consumption van either. While these rules clearly criminalise opium dens or cannabis cafes, they say nothing about the possession or consumption of other drugs. And while we’re at it, should a van even count as “premises” anyway? It is at least open to question.

Similar questions cluster around the ­later sections of the Misuse of Drugs Act invoked by James Wolffe. As the Lord Advocate told the Scottish ­Affairs ­Committee, section 9A prohibits the ­“supply” of articles for administering or preparing controlled drugs – but again, the ­detail doesn’t seem to apply to the kind of ­public health intervention ­Krykant is ­engaged in.

READ MORE: Activist opens pop-up drug tent allowing addicts to inject safely in Glasgow

Yes, the legislation criminalises the supply of “any article which may be used or adapted to be used in the administration” of a controlled drug, but the Act also makes clear that “it is not an offence” to “supply or offer to supply a hypodermic syringe” to drug users. Being in possession of naloxone – the emergency antidote for overdoses caused by heroin and other opiates – and other medical equipment is similarly no crime. So what are we suggesting? That the provision of a clean chair to sit in and a clean table to sit at is “an article used for the administration of a controlled drug”? That, at the very least, is a pretty sketchy, pretty strained ­reading of this section of the Misuse of Drugs ­legislation.

Yes, the courts have adopted a broad interpretation of the idea of being “concerned in the supply” of controlled drugs, applying the offence to a range of ­actors in the supply chain bringing drugs to ­market. But are the activists and ­volunteers working this van really doing ­anything comparable to the dealers and the distributors, the processors and the advertisers? If drug users are presenting at the van with the heroin or cocaine ­already in their possession – then where is the connection with supply?

Indeed, if Krykant’s courageous initiative is criminal under these various ­sections of the Misuse of Drugs Act – you might ask why he has not yet faced arrest, prosecution or charge under any of them, despite being in business for months, ­despite his regular interactions with ­police officers, despite the widespread press reports about what he was doing and where.

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On the October 23, Krykant was charged under the 1971 Act – but the ­detail here is important. The arrest was reported in parts of the media as a charge for “operating an illegal drugs consumption van”, but this arguably confused the issues. In a statement, Police ­Scotland said: “A 43-year-old man has been charged in connection with an offence under the Misuse of Drugs Act 1971 on Parnie Street in Glasgow.”

These reports failed to amplify the ­critical point: the arrest was for alleged obstruction of a police search of the ­vehicle – not because officers believed the provision of clean needles and a seat to sit in constituted a drugs offence. As Krykant and his backers have long argued – and as my student picked up from their studies – the law here seems much less clear than is often supposed.

Against that backdrop, I find myself growing increasingly sceptical about the supposedly “constitutional” improprieties of the Lord Advocate giving a much stronger steer to police and prosecutors about how to handle the issue. While I’ve some sympathy with Wolffe’s desire not to become a legislator or to usurp political functions which belong elsewhere – there are powerful precedents for taking a radically different approach to prosecuting, and not prosecuting, in the public interest. The cautious way is not the only way.

For nearly four decades between the 1960s and 2000, Scotland’s chief public prosecutors took it upon themselves ­effectively to ignore the law of the land criminalising gay sex in private. Until 1980, even consensual homosexual ­activity ­remained a criminal offence in Scotland. As the law in England and Wales moved on, the age of consent was not fully equalised in this jurisdiction ­until the year 2000.

And the Lord Advocates? They took the decision, one after the other, year after year, in the public interest, to ignore the law of the land. In 1991, the chief public prosecutor issued Crown Office Circular 2025 to procurators fiscal across Scotland. This circular stated that “the Lord Advocate considered that the ­public interest was not served by routinely ­prosecuting all persons who participated in those consensual homosexual acts which remain unlawful.”

This policy did not go uncriticised but the policy expressed a much more robust interpretation of the Lord Advocate’s constitutional responsibility to institute proceedings in the public interest than Wolffe seems prepared to countenance now. They were routinely ignoring the law. The demands for comfort and recognition here are much more modest.

Would it be preferable if safe injecting rules could be established by the NHS? Absolutely. Would it be better if the legal status of these activities was secured by clear ministerial orders out of Whitehall, or the devolution of drugs policy? ­Without question.

But in the absence of that legal security, as activists put their liberty and livelihoods in jeopardy to help save lives, as deaths mount, as secondary harms ­accumulate in Scotland’s cities with no sign the Westminster government is ­prepared to give an inch – its time the Lord Advocate rediscovered a bolder notion of prosecuting in the public interest.