The deaths are part of a national crisis of heroin and opioid-related overdoses, which experts have compared to the H.I.V. crisis of the late 1980s and early 1990s. Policy makers in several states, including New York, Maryland and California, are considering the kind of sites recommended by the task force in Seattle.

Kathy Lambert, a Republican councilwoman in King County, did not respond to a request for comment on the policy.

Patricia Sully, a lawyer at the Public Defender Association in Seattle and a member of the task force, said that such sites would be “a natural next step” for a city that has had a clean needle exchange program since 1989.

“Once you have a city that’s already adopted syringe exchange and is talking about these things, it makes sense at some point that people say, ‘Hey, maybe if we’re going to give people syringes, maybe we don’t send them out to a dirty alley to use them,’” she said.

The idea is not a new one. Similar facilities have operated for at least a decade in Australia, the Netherlands and Canada. In 2003, a safe-injection site called InSite opened in Vancouver, British Columbia, in response to an overdose epidemic in the city’s Downtown Eastside neighborhood. It was the first such facility in North America.

The sites are typically associated with a broader slate of what are often called “harm reduction” policies, which focus on the mental and physical health of those addicted to drugs and present an alternative to the more punitive policies associated with the war on drugs.

Liz Evans, who was the executive director of the nonprofit that operated the InSite facility in Vancouver when it opened, said it was created in response to a citywide acknowledgment that a drug policy that was tougher on addicted people was failing the city.