This week, Boston City Council signaled openness to the facilities if they become legal.

Public health leaders attributed the change to less of the potent, deadly opioid fentanyl in the drug supply.

The tentative agreement sets aside billions nationwide to fight the opioid epidemic.

“It’s an act of political cowardice,” one advocate told GBH News.

Medications approved for treating opioid use disorder — Suboxone, naltrexone and methadone — have made it possible to see progress in preventing overdoses among people reentering free society.

Recent blood tests from people who've overdosed showed an animal tranquilizer called medetomidine.

A bill up for a vote Tuesday in the state Senate includes liability protections for harm reduction sites, if cities and towns choose to open them.

Plans to add more than 800 beds, many for people recovering from addiction, drew sharp pushback at a City Council meeting Thursday.

The city of Boston announced the "Family Overdose Support Fund" for families who lost loved ones in the opioid epidemic. It's the first use of the city's payments from Massachusetts' $230 million settlement with opioid manufacturers.

State bill would permit overdose prevention centers; they are still illegal under federal law.