In science, debates are often the best forum to tackle issues where evidence supports both sides of an uncertain issue. The harms of anti-depressant medication among youth, the value of genetically modified crops, the dangers of cellphone use — these are all areas where scientific evidence is split, and for that reason debate serves society well. But there are other “debates” that are anything but scientific; debates in which the conversation isn’t between people weighing scientific evidence, but between scientific evidence and those that would prefer to deny its existence.

Such is the case with the purported “debate” around the value of supervised injection sites to Canadian society, which serves only to cloud the public’s understanding of the lopsided degree to which the scientific evidence overwhelmingly demonstrates the value of these programs.

At Insite, the supervised injection site in Vancouver that has operated since 2003, drug addicts are provided with clean needles and syringes with which to inject drugs in a medically-supervised setting. Once admitted into the site, clients inject drugs while monitored by registered nurses specially trained in addiction services. The site’s clients are provided with access to basic health services such as wound care and treatment for skin infections, and can also get help from an addictions counselour. Through the addictions counselour, Insite’s clients are encouraged to enter into drug treatment.

There are now over 30 scientific peer-reviewed studies of Insite, published in the world’s most prestigious medical journals, including The New England Journal of Medicine, The Lancet, The British Medical Journal, and many others. The collected results — which likely represent the most in-depth evaluation of any medical clinic in Canadian history — paint a portrait of a medical intervention that, by any measure, can only be described as incredibly successful. It is impossible to do justice to the scientific rigour of the evaluation and its many findings within the small space allotted. However, the evaluation has shown that Insite has reduced the rate of overdose in the surrounding neighbourhood by 35 per cent since its inception (not to mention the perfect record of zero overdose fatalities at the facility since its implementation); has dramatically reduced risk behaviours for HIV transmission such as used needle sharing among its clients; and has been associated with a decrease in drug-related disorder such as public injecting and drug litter in the surrounding area. Beyond that, research has found that visitors to Insite are more likely to enter into detox and addiction treatment compared with injection drug users in Vancouver that don’t use the site. For a facility that was implemented to reduce the direct harms of drug use like HIV transmission and fatal overdose, the fact that Insite also contributes to an increase in addiction treatment uptake speaks to the comprehensive benefits of this medical intervention.

Of course, the Huffington Post debate today is about whether taxpayers (and, by extension, the governments elected by taxpayers) should support supervised injection sites. And so the debate, for better or for worse, comes down to cost-effectiveness.

And it is in the area of cost-effectiveness that the value of supervised injection sites to Canadian society in general is best expressed. Yes, Insite saves the lives of drug users that might otherwise contract HIV through needle sharing or die of an overdose away from medical supervision. But beyond these direct benefits to drug users, the scientific research demonstrates that Canadian taxpayers are also great beneficiaries of this intervention. According to a cost-benefit study published in the globally-respected Canadian Medical Association Journal, Insite produces net savings to Canadian taxpayers of close to $20 million annually, while preventing 35 cases of HIV infection and three drug-related deaths per year. This is an astounding achievement, and illustrates the reason why the results of the scientific evaluation of Insite have been recognized and supported by the Canadian Medical Association, the Canadian Public Health Association, the Vancouver Police Department, and countless HIV scientists, criminologists, and drug policy experts across the world. In addition, upon review of this research, the Supreme Court of Canada ruled unanimously in favour of Insite in a recent case in which the Conservative government of Canada attempted to have it shut down. In a strong rebuke to the Conservative government, the Canadian justices wrote that shutting down Insite amounted to “threatening the heath and indeed the lives of the [site’s] potential clients.”

Opponents of supervised injection sites have cloaked themselves in pseudo-science to support their arguments, all the while claiming with a straight face that all of the world’s most respected medical journals somehow got it wrong on this one. My interlocutor in this debate has himself published an article on the website of Drug Free America Foundation. Imitation is the sincerest form of flattery, and in this case the shoddy imitation of scientific evidence that opponents of supervised injection sites have carted out only serves to underscore the strength of the actual scientific evidence in support of these programs. In fact, subsequent disclosures revealed that the RCMP funded Mangham’s report, and were later forced to acknowledge that it was in fact factually inaccurate.

The evidence is incontrovertible: Vancouver’s supervised injection site has been shown to save lives, reduce HIV infection, cut down on public drug use and disorder, and increase addiction treatment uptake among its clients. And, to boot, it does so in a way that saves tens of millions of dollars for Canadian taxpayers each year. No wonder the site enjoys unanimous support from the Supreme Court of Canada and widespread support among Canadians. Given this level of evidence, the debate should really be about why the Canadian federal government continues to oppose treating drug use as a public health issue. Injection drug use remains a primary mode of HIV transmission in Canada, and one case of HIV infection costs the Canadian medical system an average of $500,000. So remind me: What this debate is all about?

This post originally appeared on Huffington Post.