What Happened:

A unanimous panel of the U.S. Court of Appeals for the Fourth Circuit revived a suit against certain pharmaceutical distributors brought under West Virginia public nuisance law. The panel held that the effects of over-distributing prescription opioids may constitute a public nuisance under West Virginia law, defined distributors’ duties under the Controlled Substances Act (CSA), and held that abatement may include monetary funding to remediate alleged community harm. Notably, the Fourth Circuit’s decision comes after the West Virginia Supreme Court declined to determine the scope of West Virginia public nuisance law, and as a result, the decision refused to limit the scope of public nuisance law without guidance from the West Virginia Supreme Court.

Importantly, this opinion is not binding throughout the Fourth Circuit on all issues. Its holdings are only precedent for federal courts in the Fourth Circuit when applying West Virginia law regarding public nuisance.

The Details:

Although the decision greenlights the public nuisance suit in West Virginia, its holdings should not be overread.

First, the court rejected that public nuisance law embodied categorical “product-based” limitations. Citing the statutory definition for public nuisance — an unreasonable interference with a public right or harm to an indefinite number of people — the court determined that this open-ended text includes the sale and distribution of opioids harming public health. Even though West Virginia has a products liability cause of action, the court explained this action may not address the alleged widespread harm inflicted on the community (versus individuals) and affecting entities charged with maintaining public health and welfare. For example, the suit alleged that in one West Virginia county, more than 10% of its 150,000 residents were or had been addicted to opioids. Without an affirmative statement of West Virginia law, the court would not foreclose public nuisance on the basis that the harm arises from legal sale. Instead, the decision finds that the touchstone of public nuisance remains interference with a public right.

Second, the court rejected the district court’s reading of the distributors’ obligations under the CSA. The act requires distributors to operate suspicious order monitoring systems (SOMs) that review each individual order (size, deviations from normal patterns, and frequency), report suspicious orders, and withhold shipments absent due diligence. The district court said that these duties required only that distributors’ SOMs only identify pharmacies that operated as an “illicit adjunct.” The Fourth Circuit explained that the CSA does not impose such a limitation and that the evidence showing that certain distributors often automatically raised pharmacies’ monthly thresholds is relevant to whether distributors violated those obligations.

Third, the court rejected the district court’s view of proximate cause and the distributors’ legal duties, and instead adopted a more expansive approach to proximate cause and remoteness, but did not decide whether intervening acts sever causation here. Under West Virginia law, downstream acts by doctors, pharmacists, or diversion do not automatically break the causal chain if they were foreseeable; an intervening act must be the sole, independent cause to sever proximate causation. According to the Fourth Circuit, the district court must reconsider duty and foreseeability through the proper CSA lens. That includes evaluating individual orders and the distributors’ access to prescriber-level data: evidence showed the top 1% of prescribers in Cabell County wrote about 40% of opioid dosage units, with two “outlier” doctors collectively prescribing more than 24 million dosage units before losing their licenses. The district court must also assess how the distributors’ threshold practices and reporting decisions interacted with pharmacy ordering and outlier prescribers.

Fourth, the panel rejected the district court’s view that abatement is confined to injunctive cessation (stopping the supply of prescription opioids) and cannot entail monetary remedies. Instead, the court found that abatement may address the harmful conditions resulting from the nuisance, including that money may be an appropriate equitable remedy in West Virginia. Thus, the district court must evaluate plaintiffs’ proposed 15-year, approximately $2.5 billion abatement plan (prevention, treatment, recovery, and support for vulnerable populations) on its merits and tailor any remedy as equity requires. Additionally, the district court must determine whether any intervening causes sever proximate causation.

Its Impact:

The opinion opens the door to public nuisance claims based on product distribution rather than traditional property-based harm — but this result is specific to the court’s interpretation of West Virginia law. The court’s central message is clear — public nuisance in West Virginia is capacious, and the CSA imposes granular, order-level duties on distributors. Notably, this outcome diverges from decisions in other states, where courts interpreting their own public nuisance laws have reached different conclusions about whether product distribution can support such claim. As a result, outcomes in public nuisance cases can vary significantly depending on the state law at issue. Because the West Virginia Supreme Court has not weighed in on the scope of public nuisance in this context, some doctrinal uncertainty remains. But without more guidance, federal courts in the Fourth Circuit will be bound by the decision. What is particularly troubling is that this use of public nuisance substantially interferes with the relationship between the Drug Enforcement Administration (DEA) and distributors. Although the DEA is tasked with overseeing distributors, any judgment against the distributors may change the way distributors consider operating their SOMs. Therefore, in a regulated space, alleged violations of amorphous statutory obligations may serve as the predicate for finding “unreasonable” conduct and permitting state juries and judges to define those federal obligations.