The war on drugs is a "destructive" failure that is fuelling the transmission of HIV/AIDS, according to a former Supreme Court justice.

Louise Arbour, who has also served as UN High Commissioner on Human Rights, said a "repressive" approach to drug policies is not only a public health disaster — but a colossal waste from an economic perspective as well.

"The current cost world-wide of the law enforcement model, the repressive model, is astronomical and frankly is becoming unsustainable," Arbour told CBC News. "It's a massive industry that includes not only prisons, but increasingly heavy and sophisticated law-enforcement operations."

Arbour is a member of the Global Commission on Drug Policy, which formally released a landmark report Tuesday suggesting the criminalization of drug use is driving the global pandemic of HIV/AIDS. While the report did not drill down on the costs associated with law enforcement and incarceration, she hopes the commission will delve into the global finances in its next stage.

Arbour said political leaders must recognize that by investing huge amounts of money in enforcement and incarceration, they are depriving their governments of public health dollars that could be better applied to prevention and treatment.

Repressive drug policies that target intravenous drug users drive them underground into extremely unsafe practices that contribute to the spread of HIV/AIDS, Arbour said. One-third of new infections outside of sub-Saharan Africa are linked to intravenous drug use, she noted.

The report urges a shift in focus from treating addiction as a criminal justice issue to a public health one. Arbour said the war on drugs is putting lives at risk.

"It contributes to the spread of very deadly diseases by actually scaring people away from what should be their approach, which is to seek treatment and to the extent that their addiction is so intense that it can not be eradicated or at least not overnight, to accompany them through health practices that are safe: needle exchanges, safe injection sites … all these practices that are evidence-based rather than ideologically based," she said.

'Prohibition ... has failed'

In the report released Tuesday, the commission — which also includes six former presidents, former U.S. Secretary of State George Schultz and British business magnate Richard Branson — condemns tough enforcement policies that focus on criminalization and punishment over prevention and public health programs.

Branson called the war on drugs "perhaps the greatest failure" of public policy in the past 40 years.

"Our message is that [drug] prohibition law has failed" at preventing drug use and protecting people's health, Michel Kazatchkine, a French physician and former director of The Global Fund to Fight AIDS, Tuberculosis and Malaria, said Tuesday from London, England.

The evidence that harm reduction works is conclusive, Kazatchkine said.

The report also suggests that a tough-on-drugs policy spreads violence and leads to mass incarceration. Ruth Dreifuss, a former president of Switzerland and a co-author of the report, noted Tuesday that the policy has not reduced the supply and demand of drugs.

Canada's approach questioned

The report comes as Canada's Conservative government comes under fire for passing tough-on-drugs legislation — a policy direction that has drawn condemnation in the past from the international panel. But the report singles out positive progress in British Columbia, where public health interventions like syringe distribution, substitution programs and medically supervised injecting facilities have led to historic low rates of HIV.

"We remain concerned with all of the risks associated with the use of illicit drugs," said Julie Di Mambro, a spokeswoman for Justice Minister Rob Nicholson.

"That is why our Government is continuing its efforts under the National Anti-Drug Strategy (NADS), which focuses on prevention and access to treatment for those with drug dependencies, while at the same time getting tough on drug dealers and producers who threaten the safety of our youth and communities."

The report is being released in advance of next month's international AIDS conference in Washington, D.C.

The commissioner members include: Cesar Gaviria, former president of Colombia; Ernesto Zedillo, former president of Mexico; former president of Chile Ricardo Lagos; Aleksander Kwasniewski, former president of Poland; Fernando Henrique Cardoso, former president of Brazil and George Papandreou, former president of Greece.