For years, it was illegal to give out clean needles in Nashville. They did it anyway.

Samantha Black, 43, knocks lightly on the door of the RV, and the sound echoes inside like a faint cry for help. Black started using heroin last year, and now her addiction demands a steady stream of syringes. Clean or dirty, the addiction doesn’t care.

The RV door to the swings wide. Robert Crawford, a man with a disarming smile, beckons Black inside, where it is bright and clean like a doctor’s office on wheels.

Black drops five used heroin needles in a medical waste bucket, then Crawford hands her a red plastic bag. Inside is everything she will need: clean syringes, cotton balls, alcohol wipes and a tiny metal cooker, barely bigger than a thimble.

Black pulls a few rumpled dollar bills from her pocket, but Crawford waves them away. This is not about money, he insists.

“We don’t have anything like this in Rutherford County,” Black says, sheepishly, as she prepares to head home. “At least you know the needles are clean.”

This exchange, which not long ago was illegal, happens about 50 times a day at Street Works, a Nashville nonprofit that became Tennessee’s first state-sanctioned syringe services program in February. In the four months since then, Street Works has dispersed more than 66,000 free syringes and collected about 17,000 dirty ones, slowing the spread of HIV and hepatitis C among a growing population of heroin addicts in Nashville and surrounding counties. And this work has only become more important in the last month, as Nashville struggles with a hepatitis A outbreak in which drug users are one of the most at-risk groups.

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Tennessee lawmakers first approved syringe programs like this one last year, but it’s no secret that Street Works has operated for much longer than that. The organization has handed out clean needles in quiet defiance of state law for about a decade, and and now that their program is finally legitimate, officials at the small nonprofit office in North Nashville operate with the ultimate affirmation they were ahead of the curve all along.

"It’s just like picketing or protesting," said Thomas Gooch, who has led the syringe program since before it was legal.

"Sometimes you have to put yourself at risk to do the right thing while you wait for the law to change. And when it finally did, we were ahead. We were on the ground running.”

'Addicts are gonna use'

Syringe exchange programs, which are new to Tennessee but an established practice in other parts of the country, are intended to slow the spread of blood-borne diseases by providing drug addicts with free clean needles so they don’t share or reuse dirty ones.

Some conservative critics claim that these exchanges enable or even promote drug use, making the programs controversial in some states. But the scientific consensus is exchange programs only help contain diseases because desperate addicts will inject themselves with or without clean syringes.

Some of that criticism lingers in Nashville, Gooch said, but he laughs it off as "silly."

“Addicts are gonna use,” he says with no doubt in his voice. “There ain’t nothing someone else can say — not the news, not Donald Trump, not anybody — that is going to stop an addict from using if they want to use. But we can try to make it safer.

“That is the thing I think of every day: If I give them needles, I got a shot of them staying healthy enough that one day they might want some help.”

Before Tennessee law changed last year, Street Works was technically breaking the law by distributing drug paraphernalia, but police and city officials turned a blind eye to their operations, possibly out of sympathy for their cause. The new law, signed last May, instructed the Tennessee Department of Health to consider applications for state-sanctioned syringe programs, which, if approved, could operate with impunity and would receive a small amount of government funding. As of today, state officials have approved only three programs: Positively Living in Knoxville; CEMPA in Chattanooga; and Street Works, Tennessee’s largest syringe exchange.

But even the largest exchange still isn’t very large. Street Work's program is little more than a closet of supplies, a modified RV, a cell phone that never stops ringing and two men whose lives have been scarred by addiction. Gooch, the program leader, is a former heroin addict who joined Street Works as a volunteer eight years ago. Crawford, who was hired with state funding three months ago, grew up in a neighborhood seeped in heroin and said he has lost three friends to opioid overdoses in the past year.

They both describes Street Works as a calling.

“This doesn’t feel like a job,” Crawford says, as he hands out syringes. “I don’t wake up on Monday and not want to go to work. Most of the time, I don’t want to go home.”

Free HIV test, dose of Narcan

The syringe exchange generally works like this: Addicts call a dedicated phone number to get the location of the RV, which on most days is handing out syringes somewhere in the city. Anyone who visits the RV can also get a free HIV test or a dose of Narcan, an anti-overdose drug.

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From Street Work’s clientele, it’s clear the opioid crisis has snaked its tendrils into all walks of life. Many people assume that all addict are jobless or homeless, but Gooch says knows a teacher who would come get clean needles after school. Crawford knows a lawyer who comes to the RV wearing a suit and driving a Mercedes.

“Some of the people come here, then they go to work, and nobody knows,” Crawford said. “It’s more people than you think.”

Now that the program is legal, Street Works can also collect dirty needles, which are delivered to the Metro Public Health Department, who in turns them over to the state. The nonprofit has also begun handing out a Street Works ID card that specifically quote the new law, designed specifically to be show to a police officer in case they try to confiscate the clean needles as paraphernalia.

But legality has come with its own set of challenges too. Street Works received $45,000 of state funding this year, but per the state law the money can’t be spent on syringes or any exchange supplies. And after years of giving out syringes wherever they were needed, the nonprofit is now required to work only in state-approved locations, which must be at least 1,000 feet from all schools and parks. Street Works received approval to give out syringes in the parking lot of its own headquarters just last month.

That’s where the RV was parked on a Friday morning in May when Chris Hall, an addict in need of needles, came knocking.

Hall, who has visited Street Works about seven times over the past year, said he had witnessed how the syringe exchange has evolved from something “clandestine” to a state-sanctioned program. The transformation, he said, was "long overdue."

“The health implications are ludicrously obvious,” Hall said. “Does the state really want to spend $100,000 on somebody’s hep C treatment? Or support these guys a little bit?”

Brett Kelman is the health care reporter for The Tennessean. He can be reached at 615-259-8287 or at brett.kelman@tennessean.com. Follow him on Twitter at @brettkelman.