A Drug Test Cost a D.E.A. Agent His Job. He Sued, and Got It Back.

The Drug Enforcement Administration regarded Anthony L. Armour as an “outstanding” special agent on the front lines of the nation’s opioid epidemic. But in 2019, a routine drug test derailed his career.

Months earlier, Mr. Armour said he had begun using CBD oil, which is derived from hemp, to treat chronic pain, deeming it safer than the highly addictive painkillers that were the focus of his criminal investigations.

His failed drug test led the government to fire him, setting off a lengthy court battle that underscored the growing pains of a booming and largely unregulated CBD industry.

Last week, Mr. Armour won his case. In a rare move, the Department of Justice agreed to rehire him as a special agent, provide some back pay, cover his legal expenses and restore his eligibility for a pension.

“I’m excited to be getting back to work at D.E.A.,” said Mr. Armour, 49, who joined the agency in 2004 and is set to return to its Houston office on Monday. “I hope to finish my career at D.E.A. by helping its mission in taking dangerous drugs like fentanyl off the streets.”

The legal settlement between Mr. Armour and the Department of Justice, which has not been previously reported, comes amid a broad re-examination of the dangers and therapeutic value of cannabis.

Newly disclosed documents showed that the Biden administration is reconsidering the legal and regulatory status of cannabis following an assessment by federal scientists who concluded that the plant’s medicinal potential justifies removing it from the most restrictive category of drugs.

Cannabis use in the United States has soared in recent years as 24 states legalized recreational marijuana and 38 sanctioned its medicinal use.

A major milestone in the increasingly permissive landscape came in 2018, when Congress legalized CBD as part of the Farm Bill. It allowed CBD products that contain less than 0.3 percent THC, the psychoactive component of marijuana.

Experts at the World Health Organization issued a report in June 2018 calling CBD a generally safe and promising medicine.

In recent years, CBD has become a multibillion-dollar industry catering to people with chronic pain, insomnia, addiction and anxiety. It is infused in tinctures taken orally, gummies, sparkling sodas, bath salts, massage oil, coffee, makeup and even dog treats.

As its appeal exploded, thorny issues arose. After CBD became legal under federal law, it remained unlawful in several states, which landed CBD entrepreneurs in legal trouble. In 2020, the Food and Drug Administration found that several products sold as CBD contained more than trace amounts of THC. By then, the unreliability of CBD product labels had already become clear to some consumers, as they began failing drug tests.

Among them was Mr. Armour, who has grappled with chronic pain for years. He has said he was injured as a college football player and later at work, including in a traffic accident during a surveillance operation that left him with an acute sprain in the neck and severe back pain.

After the crash in 2016, Mr. Armour said he considered taking legally prescribed opioids, but opted not to because he had seen the dangers of opioid addiction up close. In early 2019, he ordered a vaporizer and CBD tinctures — which are taken orally — from an online retailer he considered reputable. The products eased his pain, Mr. Armour said, and he believed he had no reason to think he was taking a risk.

Under D.E.A. policy, employees found to have used illegal drugs are fired “absent extreme circumstances.”

After a routine drug test came back positive for marijuana a few months later, he told supervisors that he had been using CBD and turned the products over to investigators. Lab tests showed that two contained less than 0.3 percent of THC, but one had a slightly elevated level: 0.35 percent, which was within the test’s 0.08 percent margin of error, according to Mr. Armour’s lawsuit.

A short time later, a D.E.A. official in Houston cautioned employees to avoid of CBD products, warning that drug tests could not reliably distinguish between CBD and regular marijuana, records show.

“Please don’t create problems for yourself by using this snake oil,” the official, Will R. Glaspy, wrote in a memo emailed to staff members.

In 2020, Mr. Armour was fired.

In a lawsuit that asserted wrongful termination, Matthew C. Zorn, Mr. Armour’s lawyer, argued that his client had not intentionally used marijuana, that the D.E.A. had no explicit rules regarding CBD use by employees and that termination had been an unduly harsh punishment.

“Anthony’s case reminds us that laws relating to cannabis don’t always make sense and can be counterproductive,” Mr. Zorn said.

In a legal filing, the Department of Justice acknowledged that there was no evidence that Mr. Armour had intentionally broken the law. But the government argued that Mr. Armour should have known that CBD use could result in a positive drug test.

“Mr. Armour was an outstanding D.E.A. agent when he took a chance in 2019,” the Justice Department wrote in a legal brief submitted to a federal appeals court last year. “This was an unfortunate ending to a lengthy and productive career in federal law enforcement. But D.E.A. is charged with enforcing our nation’s drug laws, and federal employees are responsible for what they put in their bodies.”

Last September, Mr. Armour testified before Congress as lawmakers considered a bill that would have loosened cannabis use rules for federal employees. He argued that the federal government’s strict enforcement of cannabis rules was shortsighted.

“Nobody should have to choose between suffering pain and serving our country,” he said.

Earlier this month, the agency agreed to reinstate Mr. Armour and pay him $470,000 in back pay and legal costs, according to a copy of the settlement, which The New York Times obtained from the National Organization for the Reform of Marijuana Laws, a group that favors broader legalization.

It is not clear what led the government to reverse course. A spokeswoman for the D.E.A. declined to comment on the case. An agency bulletin issued to employees in 2021 does not outright prohibit the use of CBD products. But it warns that the fact that they can be bought legally “is not a defense against” a positive drug test.

For his part, Mr. Armour says he continues to see value in using CBD for pain management. Once he returns to work, he said, “I am going to consult a medical professional about my options.”