Philip Owen, who became a strong advocate for the Insite program during his nine-year term as Vancouver's mayor, says there is "no doubt the evidence in the world supports what (Coderre) is trying to do" and what Vancouver was successful in doing.
Owen said Montreal is going to face a fierce battle with the federal government but he said Coderre should "just keep pushing ahead."
"We looked at this whole issue and decided, quite simply, that the user is sick and the dealer is evil, so put the user in the health care system," Owen said, citing that injection sites are used as a public health measure all over Europe.
The ongoing debate over drug-injection sites in Canada is gaining momentum this summer as a high-profile deadline looms for the feds.
Montreal has given the federal government until the end of the summer to respond to the city's request for legal approval for three fixed sites and a mobile unit.
But Coderre has already slammed the process as a "formality" and vows to proceed with or without the federal green light.
Health Minister Rona Ambrose is using the spat with Montreal to take aim at Liberal Leader Justin Trudeau, who once served with Coderre in the Commons when Montreal's mayor was a Grit MP.
"Our government will make sure that residents of Montreal get a say when injection houses want to open, in keeping with the Supreme Court's ruling," Ambrose said in a statement. "We oppose and are deeply concerned with Justin Trudeau's pledge to open drug injection houses in communities across Canada."
In a 2011 decision, the Supreme Court ruled Insite saved lives and improved health without increasing drug use and crime in the surrounding area.
The court also said the government should “generally grant an exemption” required to legally operate a supervised injection site if the evidence indicates it will decrease the risk of death and disease and it will have little impact on public safety.
The Conservative government then passed the Respect for Communities Act, which establishes 26 criteria for the government to consider when reviewing an application.
Several health groups, including the Canadian Nurses Association, argued the new law is designed to block the creation of supervised injection sites.
Health Canada said it would be up to law enforcement, in charge of investigating contraventions of the Controlled Drugs and Substances Act, to address sites that proceed without a legal exemption.
Dr. Mark Tyndall, the director of the UBC Centre for Disease Control, said it seems unnecessary the federal government should have any say in what a city does to engage people with addiction.
"I think it is a good move by the mayor of Montreal and the people supporting that," he said. "The main divide is the federal government still views this as crime and punishment ... For those of us that have been on the ground for years, it is quite obvious that is not the way to deal with this."
Vancouver Coastal Health, which runs a number of programs including Insite, said it is backing Montreal's efforts because there is "no doubt of the likely benefits to intravenous drug users living in Montreal.
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