Walmart sues federal government over opioid case

Walmart is throwing the first punch in what could be dueling lawsuits with the federal government about the retailer's alleged role in the opioid epidemic.

Walmart, which runs one of the largest pharmacy chains in the U.S., filed its lawsuit on Thursday because it says the U.S. Justice Department is threatening to sue it , claiming pharmacists should have refused to fill otherwise valid opioid prescriptions.

Opioid addiction is responsible for roughly 400,000 deaths in the United States from 1999 to 2017, according to the U.S. Centers for Disease Control and Prevention.

The retailer says it is seeking clarity on the roles and legal responsibilities of pharmacists and pharmacies in filling opioid prescriptions.

"We are bringing this lawsuit because there is no federal law requiring pharmacists to interfere in the doctor-patient relationship to the degree DOJ is demanding," Walmart said in a statement.

Walmart in the lawsuit also takes issue with allegations made by the DOJ and the Drug Enforcement Administration that the retailer failed to submit suspicious opioid order reports, for which the government is seeking financial penalties.

The DOJ and DEA did not immediately respond to request for comment.

The U.S. government has been going after companies for their alleged role in an opioid crisis that the Trump administration has declared a public health emergency.