A version of this article originally appeared on VICE UK.

Lisa chops the heroin into a small beige line, about three inches long. She lifts it to her face and snorts it with expert precision. Then she turns and smiles. "Much better. Would you two like another cup of tea?"

The heroin we've just watched Lisa snort is no ordinary street smack. This is heroin supplied by the British state—prescribed to Lisa by her doctor, and provided by a pharmacist. It is completely pure, and to get it Lisa didn't need to encounter a single drug dealer, gangster or criminal.

There is so much controversy any time a so-called "progressive" approach to drugs is attempted in Britain—from safe consumption facilities to medical cannabis for suffering children—that the idea of people being prescribed heroin, rather than even methadone, to manage their addiction seems almost fantastical. Yet, Lisa is one of the last remaining remnants of a foundational tradition in British drug policy. The practice of prescribing heroin to manage addiction was originally invented in the UK—and was so entrenched here that it was formally known in international policy circles as the "British System". Throughout the early 20th century, as America began forcing its War on Drugs on the rest of the world, it was Britain that represented the most promising alternative model. The story of the British System, and of how it was dismantled under American pressure, has been all but forgotten. It shouldn't be. This story illuminates not only fascinating truths about drug policy, but about entire liberal traditions in British political history.

Throughout the 19th century opium was imported to Britain and sold everywhere from high street pharmacies to rural grocery stores. This was all completely legal. Most people used laudanum (a tincture of morphine and codeine) purely as a medicine. A few, such as the writers Samuel Taylor Coleridge and Thomas De Quincey, took opiates seeking pleasure and mind expansion. Queen Victoria was fond of both opium and cannabis, before being introduced to cocaine later in life.

As technology and trade progressed, new professions emerged. Old-fashioned apothecaries gave way to a new class of professional pharmacists, and in 1868 the Pharmacy Act placed opium under pharmaceutical control with minimal regulation.

Britain emerged from the First World War a nation transformed. Women got the vote, and the first governmental Ministry of Health was founded in 1919. Debate immediately began on whether the medical profession or the Home Office should take the lead in the regulation of drug use.

The United States, the rising power on the world stage, had banned all drugs with the Harrison Narcotics Tax Act of 1914, and was strongly pushing their moralizing, prohibitionist approach across the world. This received furious opposition from the British medical community. In 1923, WE Dixon, reader in pharmacology at Cambridge, wrote to The Times:

We do not seem to have learnt anything from the experience of our American brethren … cannot our legislators understand that our only hope of stamping out the drug addict is through the doctors, that legislation above the doctors' heads is likely to prove our undoing and that we can no more stamp out addiction by prohibition than we can stamp out insanity?

In 1924, a committee was formed to consider these questions, under the leadership of Sir Humphry Rolleston, President of the Royal College of Physicians. The result was the British System. Doctors could use their own discretion in prescribing heroin to treat addiction, with loose overall control remaining with the Home Office.

What is probably most striking about the discussions of the Rolleston Committee is their utter sobriety. There is not a hint of the moralizing hysteria that characterized conversations around drugs in America. Addiction is spoken about as an "unfortunate condition"—but never as "evil", never as a moral failure. And for about five decades, the British System was relatively successful. Between 1936 and 1953, the number of known drug addicts in Britain fell from 616 to 290, before rising again to 454 by 1960.

The idea of a Britain in which drug addicts could be numbered in the hundreds seems almost inconceivable today. At the same time in the US, with its prohibitionist model, the addict population was skyrocketing into the hundreds of thousands.

There is a very simple reason for this. Heroin addiction tends to spread through the black market—one addict introduces another to the drug, usually in order to finance their own habit. Under a system where users receive their drugs on prescription, there is simply no need to push the drug on anyone else.

The British System completely prevented the growth of the gangster-led black market that drove the spread of addiction in the US. One widespread rumor was that, in 1963, several New York mafia crime families came to London and met at the Hilton Hotel to discuss whether they should develop a drugs syndicate in the UK. They ended up deciding there was no point. Why bother when British doctors were already supplying the drugs?

Drug addiction in the era of the British System was confined to a tiny, insular community, largely centered around London's Soho. Unfortunately, almost all the denizens of this underground scene are long gone, but we did discover a memoir written by one user, who wrote under the pen name Barbateboy:

All of the drugs I used were obtained legally on doctor’s prescription from a clutch of chemists around London. There was Boots at Piccadilly, Blisses in Kilburn, John Bell & Croyden in Wigmore St.

Very few chemists stocked these drugs and so over time I ran into most junkies who were ‘scripping’. It was a small world… A camaraderie existed and we would gossip and discuss which doctors were cool and which were severe.

The drugs were of course pure, British Pharmaceutical…The heroin came by the grain (which is about one sixteenth of a gram), consisting of six tiny tablets called jacks, which perhaps gave rise to the expression ‘To jack up’. On private prescription it cost one and tuppence a grain, the cheapest hit in town. Half a jack was as much as a non-user could stomach... Fresh syringes and needles came with every ‘scrip’. There was very little reuse. I met many people, from taxi drivers to set designers, who held responsible jobs and lived otherwise normal lives.

The British heroin scene in this era was so small that we know the precise addresses of the pharmacies where addicts picked up their gear. Almost every account of this period stresses the importance of Boots at Piccadilly Circus and John Bell & Croyden in Wigmore St. These two chemists controlled most of the British heroin supply. Reflect on that for a moment—there was a time in living memory when the two biggest heroin dealers in Britain both had W1 postcodes, didn't engage in gang wars and paid their taxes every year.

The other crucial difference between life under the British System and American-style prohibition is that there was absolutely no link between addiction and other forms of criminality. When you get your prescription from a doctor, there is simply no need to steal to fund your habit.

When the American journalist Edgar May came over to report on the British System he wrote, "No one in England—from the toughest London detective to the most liberal-prescribing clinic physician—suggested to me that narcotics addiction increases criminal behavior… in England there is no cause-and-effect relationship." The creation of a criminal addict underclass seems to only emerge under a system of drugs prohibition.

By 1959, the number of known heroin addicts in Britain had dropped to 59, before rising to 342 by 1964. By today's standards these numbers are almost comically low. On all evidence, the British System seemed effective in preventing the spread of addiction and associated criminality. So what happened? How did it all fall apart?

Left: David Pearson/Alamy Stock Photo; Right: Feng Yu/Alamy Stock Photo

Ultimately, the answer is that, in 1961, Britain was pressured into signing the UN Single Convention on Narcotic Drugs—a US-led policy formally committing every member state to prohibition. The American architects of the War on Drugs despised the British System, and constantly briefed against it in policy documents and propaganda. It was thus inevitable that the British System would come under sustained diplomatic attack. But the immediate trigger for the breakdown of the system can actually be traced back to one rogue doctor in London.

Lady Isabella Frankau is a fascinating character. Trained in psychiatry, she began treating addicts in 1957. She prescribed without question. Any addict could come to her, claim they had lost their tablets—or that their usual NHS doctor was on holiday—and she would scribble out a new script.

Word went round the addict networks like wildfire, and Frankau became a magnet for hundreds of heroin users. When the great American jazz trumpeter Chet Baker came to London, she was his first stop. "She simply asked my name, my address and how much cocaine and heroin I wanted per day," he later recalled.

But Lady Frankau was no drug dealer. She was described by other doctors as a "well-meaning fool", but no one has ever suggested she prescribed for money. In fact, she often waived her consultation fee for poorer patients.

Unfortunately, some of those patients had no such scruples. Some addicts realized they could pick up extra supplies from Frankau, then sell them on. The writer Alexander Trocchi became notorious for this on the underground scene. This was the first emergence of a "grey market" in Britain—drugs acquired legally, but sold illicitly.

Then, in 1967, Lady Frankau died. In an instant, the hundreds of addicts who had relied on her were cast adrift. Into this gap in the market stepped the shadowy figure of Dr John Petro. Originally a brilliant doctor, Petro had been one of the first to administer penicillin with Alexander Fleming. Then, in 1966, he was injured in a road accident and, unable to practice, was facing bankruptcy.

Unlike Frankau, Petro wrote prescriptions to survive. He didn't even have an office, but would hold court at all-night coffee bars in Soho or the café at Baker Street Station, scribbling out prescriptions on napkins and cigarette packs.

Inevitably, someone tipped off the papers. The Sun and the Daily Mail both led with front-page stories: "Doctor Holds Drug Clinic In A Café" and "Drugs Clinic In Station Buffet". Over the next few months, Petro's chaotic practice became an incessant tabloid circus. Finally, in January of 1968, Petro was invited onto David Frost's TV program to explain himself. Immediately after the broadcast, he was arrested.

As easy as it is to blame rogue figures like Frankau and Petro, though, they were actually dealing with a problem of the government's own making. In 1964, following American pressure, legislation had passed that doctors would now need a special license from the Home Office to prescribe heroin, but that new treatment centers would be built to compensate. Those treatment centers were never built. And it was into this gap that the British black market was born.

Dr AJ Hawes, one of the major "junkie's doctors" of the era, wrote to The Observer in 1965, warning that "to cut off supply by prescription would be easy; it has already been done in the United States, where doctors are not allowed to prescribe for addicts, with the result that the provision of drugs has become a flourishing industry and addiction there increases yearly".

Unfortunately, this is exactly what happened. Instead of fixing the problem of rogue doctors over-prescribing, the government pressured doctors doing valuable work. Addicts could no longer get prescriptions, so illegal heroin began trickling into the country to satisfy demand. Unlike America, this did not come from Italian mafia organizations, but from Chinese Triads working out of Hong Kong. Little red packets of south-east Asian heroin, stamped with an elephant design, began littering the gutters of Gerrard Street in London's Chinatown.

We can pick up this story in the memoir of the anonymous addict, Barbateboy, that we followed earlier:

The tabloid press had got all judgmental about the practice of prescribing drugs. [Harold] Wilson’s government, impotent in other respects, needed to be seen as effective … almost overnight all junkies were cut off from their supplies.

The contraband trade in Chinese heroin mushroomed. Nothing pure about it. A wrap of brown, white and black (unrefined opium) powder which had to be ground and then boiled in a spoon and sucked into the syringe through a wodge of cotton wool. There was no way to assess the strength of the dose. Over the next year I lost about six friends to overdose, all experienced junkies. The whole junkie scene exploded. It became a ‘pushed’ drug, and the number of users grew as they got younger.

The key phrase here is that heroin became a "pushed drug". Under the British System there was simply no financial incentive for gangsters to import the drug, or for one user to introduce it to another. As soon as heroin is outlawed, the potential profits of a black market become almost limitless. Dealers have a huge incentive to actively get more people addicted, and the easiest way for any user to finance their own habit is to sell a bit themselves. It is a pyramid structure in which every link in the chain is incentivized to introduce more people to the habit.

By 1971, when the Misuse of Drugs Act was finally passed, there were just over a thousand known heroin addicts in the UK. Over the following decades of prohibition, the black market would rocket that number into the hundreds of thousands.

But the British System wasn't killed completely. Even under the terms of the Misuse of Drugs Act, it is still technically legal for a doctor to prescribe heroin to patients in the UK. Instead of banning it outright, the government pulled a classic bureaucratic fudge—they made doctors apply for a special license, then stopped issuing them.

Lisa, who we watched snort her government supplied heroin, first got her prescription in the 1980s, at one of the last surviving Rolleston-era drug clinics, which had been bumping along under the radar since the 1920s.

She has maintained that prescription to this day. Before the script, Lisa lived an intensely chaotic life, selling gear to prostitutes to finance her own habit. She now works full time, owns her own flat and speaks lovingly of her daughter and granddaughter—neither of whom have ever touched illicit drugs. She credits this change in her life to one thing and one thing only: the precious slip of paper she gets from her doctor that allows her to live a relatively normal, productive life.

Lisa is a living fragment of a lost history. When Switzerland introduced Heroin Assisted Therapy to great success in the 1990s, they explicitly modeled their methods on the British System. Yet, almost no one in Britain itself is aware of this story. They should be.

Britain was once a world leader, building on a humane, liberal and pragmatic tradition to show an alternative route to the cruel and failing War on Drugs. With a little imagination and courage from its leaders, it could lead the world once again.

This article contains extracts from the book Drug Wars, published by Ebury Press.

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