The study by Stephen Gaetz, director of the Canadian Homelessness Research Network, pulls together research from across Canada and the United States, which suggests it's far cheaper to give a homeless person a place to live than to provide a patchwork of emergency services.
Gaetz says governments spend at least $4.5 billion a year dealing with homeless people, including the costs of emergency health care, mental-health services, law enforcement, shelters and food banks.
That's because their use of the health system is high and unpredictable, because they often have run-ins with the law and because upon release from jail, they often end up homeless again.
Recent research done through the Mental Health Commission of Canada shows that providing support and housing to chronically homeless people can save taxpayers 54 cents on the dollar compared with the current approach.
But while the solutions are becoming more obvious, the challenge is to make them happen.
"Even when people don't like the present, they're often reluctant to make the change," Gaetz, an associate professor at York University, said in an interview. "The tide is turning however. I think they will do it in time."
The trouble is, "they" are wide array of departments at different levels of government, a hodge-podge of volunteers, churches and charities, as well as the private sector.
They all experience higher costs because of their fragmented way of dealing with homelessness, but there is no obvious way for them to collaborate in a way that would trim costs and deal more effectively with the problem, Gaetz said.
"That's a problem with governments. Doing that kind of joined-up thinking is difficult."
The network he leads brings together researchers, non-profit organizations and government officials in an effort to find out more about the homeless in Canada and confront the problem. It is partly funded by Ottawa.
The federal government has resisted increasing its involvement in affordable housing and repeatedly turns down proposals for a national poverty strategy. It wants the provinces to take on those roles, arguing that they are closer to the ground.
However, the correctional system is a major challenge for homelessness, says Gaetz, and the federal government has an undeniable role in that area.
He cites research showing that homeless people are far more likely to be arrested and jailed than people who are housed. And often, these people are released without adequate support — winding up homeless again and at a higher risk of re-offending.
The costs of the vicious circle are high for police, for the correctional system and for the individuals, Gaetz says. One study shows that taxpayers pay between $66,000 and $120,000 to cover the basic annual costs for prison or psychiatric hospitals for just one homeless person.
The room for savings is ample, Gaetz's research shows.
He points to interim findings from the mental health commission's At Home pilot project. It shows that providing mentally ill homeless people with a home and the right kind of social supports saves about $9,390 per person annually.
For chronically homeless people who are frequent users of social services, the annual savings are $25,899 per person.
The savings are substantial enough for a so-called "housing first" approach to homeless to take root in many communities across Canada — despite the difficulties governments and departments have in collaborating, says Tim Richter, who heads the newly formed Canadian Alliance to End Homelessness.
"You start with some local work-arounds," he said.
In Calgary, for example, advocates for the homeless worked with local police, who enlisted social workers to single out and prioritize people with mental-health problems.
"There are a lot of different ways to peel the onion," he said.
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