The U.S. opioid epidemic has unfolded in deadly waves, beginning with prescription painkillers, surging with heroin and accelerating further with the synthetic opioid fentanyl.
Some signs suggest overdose deaths are finally starting to decline. Overdose deaths dropped by 10 percent overall between April 2023 and April 2024, and deaths involving fentanyl dropped by 12 percent. But national statistics inherently mask regional trends, such as quickly rising fentanyl-related deaths in Western states.
“I’ve been working in harm reduction for over 20 years,” says Haven Wheelock, who runs a syringe exchange program for Outside In, an Oregon-based nonprofit organization. “I have never in my career seen a shift in drug supply—in how people are engaging with drugs, how they are using them—as quickly as I have over the last three years.”
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In February 2021, the Drug Addiction Treatment and Recovery Act (also known as Measure 110) went into effect in Oregon, making it the first U.S. state to decriminalize hard drugs. Wheelock, who led this ballot initiative and secured funding for her program with the new system, called it a brave effort to try something new, given the failure of the Nixon-era war on drugs and policing as a solution to addiction. Under the new system, people carrying small amounts of drugs such as heroin, methamphetamine and fentanyl were given a $100 fine—essentially the cost of a parking ticket—instead of being arrested.
But this experiment ended last month when Oregon recriminalized drugs after overdose deaths skyrocketed—by 41 percent within a year of Measure 110, compared to 13 percent nationally—and voters soured on decriminalization. A new study in JAMA Network Open contests the narrative that decriminalization caused this spike and instead suggests that it had no impact. Previous research from Wheelock had similar findings, but the new study also found that the arrival of fentanyl in Oregon could explain the increase in the state’s overdose deaths.
“This is the study that we were all waiting for,” says Todd Korthuis, chief of addiction medicine at Oregon Health & Science University, who was not involved with this study. Rather than decriminalization causing the spike in deaths, “fentanyl was the whole story,” he says. Other factors, such as a lack of access to treatment, only exacerbated the situation. “We need to do a better job lowering the barriers to begin methadone treatment, buprenorphine treatment”—gold-standard therapies for opioid use disorder—“and creating pathways and systems that support staying on these medications,” Korthuis says.
The new study was funded by the National Institutes of Health and Arnold Ventures, a philanthropic organization that supported Measure 110’s passage. But Brandon del Pozo, the study’s senior author and a public health researcher at Brown University, says that Arnold Ventures had no role in initiating this research nor any input into the analysis.
Using data from forensic laboratories, del Pozo’s team first showed something obvious: across every state, as fentanyl began to saturate drug markets, overdose deaths jumped up in response. In New England, fentanyl’s inflection point came around 2014; in Oregon, it happened in early 2021—right as Measure 110 came into effect.
To disentangle these effects, del Pozo’s team analyzed how much overdose deaths increased after each state’s unique fentanyl saturation point. With data from 48 states that never decriminalized drugs, the team estimated that fentanyl should have caused Oregon’s drug overdose rates to increase from 11 per 100,000 deaths in early 2021 to 18 per 100,000 in late 2022. Oregon’s actual data lined up almost perfectly with this prediction, and follow-up analyses confirmed that after accounting for fentanyl, there was no association between decriminalization and overdose deaths.
Washington State offered a natural counter-experiment to Oregon: fentanyl dominated both states around the same time, but Washington actually recriminalized drugs in 2021 after a four-month stint without criminal penalties. “If you really believe that it was decriminalization that was driving overdoses, you should see them moderate or level off after recriminalization,” del Pozo says. “Instead overdoses just accelerated” because of fentanyl after Washington’s recriminalization.
Keith Humphreys, a psychologist and co-director of the Stanford Network on Addiction Policy, who was not involved with the new study, cautions against reading too much into the Washington experiment because the decriminalization period was so brief and unusual. But he’s also skeptical of the study’s main finding. “There’s an inference there that’s probably wrong, which is that rapid spread of fentanyl is totally unrelated to policy,” Humphreys says. Decriminalization, for instance, might have increased access to fentanyl across Oregon, especially given the open-air drug markets that popped up in recent years, he claims.
While del Pozo agrees that Measure 110 impeded the state’s ability to disrupt these markets, he disputes the idea that policing could have meaningfully slowed down fentanyl or that Oregon faced anything unique. “Fentanyl has run rampant through the nation, state by state, regardless of how aggressively communities policed it,” says del Pozo, who is also a former chief of police of Burlington, Vt. “If you mapped states’ fentanyl percentage and their overdoses and took the labels off, you couldn’t tell Oregon apart from most other states.”
Ultimately, fentanyl overwhelmed any policy effect in Oregon, but the conclusion from this study shouldn’t be that the criminal justice system doesn’t matter, del Pozo adds. After all, fentanyl supplanted heroin across the U.S. partially because of the “iron law of prohibition,” in which outlawed drugs tend to get more concentrated and deadlier as traffickers create more compact, easier-to-smuggle alternatives. This makes drugs more potent and deadly over the long term, although this risk must be weighed alongside other factors such as community harms of unchecked drug dealing, del Pozo says.
Humphreys disagrees with this “iron law” because it suggests that there is something absolute and distinctive about illicit substances, even though potency has also increased in legal drugs, such as cannabis and wine. In other words, there are various market incentives to increase potency, and Humphreys argues that decriminalization won’t necessarily make the drug supply safer.
The main lesson from Oregon might be that decriminalization isn’t just an off switch and that, to succeed, it must be thoughtfully accompanied by well-funded prevention and treatment programs, according to del Pozo. For example, Portugal, which decriminalized all drug use in 2001, spent about two years working out how to implement the strategy and build up treatment capacity before it officially changed its law. Portugal also struck a balance in regulating drug possession by neither fully legalizing it nor making it a crime, avoiding the dangers at both extremes, del Pozo says.
Oregon, on the other hand, decriminalized drugs on an expedited timeline, driven by advocates “who believed in it so passionately and didn’t want the status quo to live another day,” del Pozo says. “We are in this mess with decriminalization because people were very quick with the victory lap and took their eye off other key ingredients to success.”
For example, in 2020 the National Survey on Drug Use and Health ranked Oregon the worst state in the country for access to addiction treatment. While Measure 110 allocated more than $300 million to address that, the majority of these funds only became available 18 months after the state’s decriminalization law went into effect. And these funds didn’t really go into traditional treatment services, Korthuis says.
Instead they primarily went to harm-reduction and community-based organizations, which offer clean needles, syringes and other drug paraphernalia; testing for bloodborne diseases such as HIV; the opioid reversal drug naloxone; and other supportive services. They can be “game changers for reaching people who are not looking for treatment,” Korthuis says. But without simultaneously expanded access to evidence-based medications or integrating services, many Oregon residents who wanted to access addiction care simply couldn’t.
Addressing addiction also requires tackling some of its root causes, such as poverty and homelessness. “Addiction is a maladjusted coping mechanism,” Wheelock says. “I want to make sure people have food in their bellies, roofs over their heads, loving communities surrounding them, where they’re not afraid of violence.” She thus critiques the “magical thinking” that one policy could fix addiction and what she believes is a cynical effort to scapegoat decriminalization.
Whether a policy failure or a public relations one, Oregon’s flawed experiment may already be setting back reform efforts nationally. “I’ve talked to a lot of state legislators, and the first thing they say is that ‘I don’t like the way things are going in Ohio, but we don’t want to be like Oregon,’” Humphreys says. Even though this study suggests that decriminalization didn’t significantly affect overdose deaths, he’s skeptical that it will change much because “Measure 110 wasn’t sold to voters on the argument that ‘This shouldn’t make things much worse.’”
For many of these reasons, if Wheelock could go back, she would have slowed down the timeline on decriminalization to get it right. “I hate saying that,” she says, “because people are dying and going to jail, and those are tragic outcomes.”
For Korthuis, what Oregon needs now is to double down on prevention, naloxone distribution, harm reduction and expanded treatment access, with law enforcement being part of the solution as well. “This requires an all-hands-on-deck approach from the entire community.”