After its opioid painkiller helped cause the nation’s drug overdose crisis, the family behind OxyContin allegedly wanted to try a new venture: addiction treatment.

The plan was titled Project Tango, according to recent lawsuits against the Sackler family and its company Purdue Pharma and a New York Times story by Danny Hakim, Roni Caryn Rabin, and William K. Rashbaum. It was a scheme, in short, to profit from solving the same crisis that the Sacklers and Purdue helped cause.

“Pain treatment and addiction are naturally linked,” one of the documents said.

The document included a graphic of a funnel, with “pain treatment” at the top and “opioid addiction treatment” at the bottom — a tacit admission that as more people were funneled into pain treatment via OxyContin and other painkillers, more would need addiction care.

The company briefly ditched the idea in 2014, the Times reported. But since then, the Sackler family and Purdue have considered offering formulations of the opioid overdose antidote naloxone and the opioid addiction medication buprenorphine, which is, along with methadone, viewed as the gold standard for opioid addiction treatment.

Representatives for different Sackler family members told the Times that the lawsuits were “filled with claims that are demonstrably false and unsupportable by the actual facts.” They’re planning a response to the Massachusetts lawsuit later this week.

In its defense, the family argued to the Times that the lawsuits “ignore the fact that the Sackler family has long been committed to initiatives that prevent abuse and addiction,” citing as one example donations to an addiction research and treatment center in Tulsa, Oklahoma. But as the Times reported, this $75 million contribution is only happening as part of a recent settlement with Oklahoma in another opioid epidemic lawsuit — essentially, the Sacklers are trying to take credit for what they were forced to do.

The statement also claimed that “no board member proposed Tango, or authored any documents in support of it.” But at least Kathe Sackler — a member of the Sackler family and a Purdue board member — was allegedly involved in reviewing the concept, according to New York state’s lawsuit.

The allegations that Purdue and the Sacklers tried to benefit from the same addiction and overdose crisis that they helped cause is just the latest in the literally hundreds of lawsuits that have been filed against the company, family, and other opioid makers in recent years. Several states are suing individually. A separate collection of about 1,600 lawsuits, largely from various levels of government, has been consolidated by a federal judge in Cleveland in an attempt to reach a landmark legal resolution to the opioid epidemic.

Since 1999, more than 700,000 people in the US have died of drug overdoses, mostly driven by an increase in opioid-related deaths. That’s comparable to the number of people who currently live in big cities like Denver and Washington, DC. Some estimates predict that hundreds of thousands more could die in the next decade of opioid overdoses alone.

The hope is to not just hold Purdue, the Sacklers, and others allegedly involved in the opioid epidemic accountable for the crisis but also force them to pay for addiction treatment that could help combat the epidemic. Addiction treatment is notoriously underfunded in the US, with experts in recent years calling on the federal government to invest tens of billions of dollars in building up treatment infrastructure. (For reference, a 2017 study from the White House Council of Economic Advisers linked a year of the opioid crisis to $500 billion in economic losses.)

There’s good evidence, too, that opioid makers are the right target for legal action.

How opioid makers helped cause the opioid epidemic

The opioid epidemic can be understood in three waves. In the first wave, starting in the late 1990s and early 2000s, doctors prescribed a lot of opioid painkillers. That caused the drugs to proliferate to widespread misuse and addiction — among not just patients but also friends and family of patients, teens who took the drugs from their parents’ medicine cabinets, and people who bought excess pills from the black market.

A second wave of drug overdoses took off in the 2000s when heroin flooded the illicit market, as drug dealers and traffickers took advantage of a new population of people who used opioids but either lost access to painkillers or simply sought a better, cheaper high. And in recent years, the US has seen a third wave, as fentanyls offer an even more potent, cheaper — and deadlier — alternative to heroin.

It’s the first wave that really kicked off the opioid crisis — and it’s where marketing for opioid painkillers is likely most relevant. Multiple studies have now linked marketing for opioid painkillers to addiction and overdoses, particularly direct marketing to doctors that encouraged them to prescribe more of the drugs. And another study linked an increase in the supply of opioid painkillers to more overdose deaths.

Beyond the research, we’ve also seen more reports over the past few years about opioid companies aggressively marketing their products, even as it became clearer that the drugs weren’t the safe, effective alternative to other painkillers on the market that they claimed the opioids to be.

Recently, a filing in Massachusetts Attorney General Maura Healey’s lawsuit against Purdue exposed how Richard Sackler, then Purdue’s president and part of the family that owns Purdue, was personally involved in some of those efforts. The filing claims that Sackler pushed to market OxyContin as a “non-narcotic” in other countries, even though it’s an opioid; Robert Kaiko, who created OxyContin, had to talk him down from the idea.

The company also allegedly overlooked excessive prescribing in the US, even as some of Purdue’s staff warned of pill mills that should have been reported to federal officials, Maia Szalavitz reported for Tonic.

Purdue countered that the filing “is littered with biased and inaccurate characterizations of these documents and individual defendants, often highlighting potential courses of action that were ultimately rejected by the company.”

Other reports, however, suggest opioid companies were widely irresponsible. As a group of public health experts explained in the Annual Review of Public Health, opioid companies exaggerated the benefits and safety of their products, supported advocacy groups and “education” campaigns that encouraged widespread use of opioids, and lobbied lawmakers to loosen access to the drugs. Purdue, as the maker of the then-new OxyContin, played a big role in these efforts, but so did companies like Endo, Teva, and Abbott Laboratories.

The result: As opioid sales grew, so did addiction and overdoses.

It’s not just that the drugs were deadly; they also weren’t anywhere as effective as Purdue and others claimed. There’s only very weak scientific evidence that opioid painkillers can effectively treat long-term chronic pain as patients grow tolerant of opioids’ effects — but there’s plenty of evidence that prolonged use can result in very bad complications, including a higher risk of addiction, overdose, and death. In short, the risks and downsides outweigh the benefits for most pain patients.

Yet even as these risks became apparent over the years, drug companies continued marketing the opioids. (Purdue didn’t stop advertising opioids to doctors until last year.) So different levels of government are now trying to hold the companies responsible — and get them to pay to help fix the mess that they contributed to. The Sacklers, meanwhile, seem to be trying to find other ways to profit from the crisis.

For more on the lawsuits against opioid companies, read Vox’s explainer.