The US Department of Justice announced Tuesday that it had filed a nationwide lawsuit against Walmart, Inc., alleging that the retailer had unlawfully dispensed opiates from its national pharmacy chain in violation of the Controlled Substances Act. The DOJ’s suit includes a request for injunctive relief in addition to complaints of hundreds of thousands of Controlled Substances Act violations, which could result in billions of dollars of civil penalties against Walmart.

The Controlled Substances Act (CSA) was first enacted in 1971 and places all controlled substances into five schedules of drugs that are tiered based on the likelihood of dependence, the medical utility of the drug, and the risk to public health of the drug, among other factors. Penalties for the unlawful distribution of scheduled drugs can be severe, including time in prison and heavy fines.

The CSA mandates that prescription opiates be distributed according to stringent regulations and only by registered distributors such as pharmacies. However, the DOJ has alleged that Walmart violated these requirements by filling thousands of opiate prescriptions that were not issued for legitimate medical purposes and also failed to report suspicious opiate orders as required by 21 U.S. § 832 of the CSA.

Each unlawful prescription filled could carry a penalty of nearly $68,000, and each suspicious order not reported could carry a penalty of $16,000. The DOJ has also announced that it hopes the granting of injunctive relief will prevent the possibility of further CSA violations.

In a strongly-worded press release, Walmart rejected the allegations, stating that the DOJ’s suit was “riddled with factual inaccuracies and cherry-picked documents taken out of context.” Walmart asserts that its pharmacists regularly blocked thousands of “questionable” doctors from having their prescriptions filled at Walmart and that they sent the US Drug Enforcement Agency (DEA) thousands of investigative leads regarding opiate enforcement. Walmart has also stated that it plans to challenge the lawsuit in court.