A Virginia doctor who was sentenced to federal prison for prescribing over half a million opioids to hundreds of patients in less than two years has had his sentence overturned thanks to an error in jury instruction during the initial trial.

Dr. Joel Smithers, 41, was sentenced to 40 years in federal prison in October of 2019 on hundreds of counts of illegally prescribing controlled substances after patients from Virginia and surrounding states reportedly received pills without a proper physical exam or medical records, according to the U.S. Drug Enforcement Agency (DEA).

On Friday, however, this conviction was overturned by the 4th U.S. Circuit Court of Appeals in Richmond, Virginia, citing jury instruction that misstated the law, Reuters initially reported.

During instruction, the jury was told that the prosecution needed to prove that Smithers prescribed the pills "without a legitimate medical purpose or beyond the bounds of medical practice." However, a 2022 U.S. Supreme Court decision found that proving the prescription of controlled substances as a crime requires a "knowing or intentional" act of unauthorized use on the part of the prescriber.

The federal appeals court found that the instructions given at the time were improper and a "not-harmless error," leading them to throw the conviction out, ordering a new trial for Smithers.

The office of U.S. Attorney Christopher Kavanaugh told USA TODAY in a statement, “We understand the 4^th Circuit’s decision following a recent change in the law and look forward to retrying the defendant.” Smithers' attorney did not immediately respond to a request for comment.

Dr. Joel Smithers' 2019 conviction

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Smithers was originally convicted in May 2019 of more than 800 counts of illegally prescribing controlled substances, one count of maintaining a place for the purpose of illegally distributing controlled substances and one count of possession with the intent to distribute.

He was sentenced to 40 years in prison and ordered to pay a $86,000 fine in October of that year.

Smithers was accused of prescribing controlled substances including oxymorphone, oxycodone, hydromorphone and fentanyl to every patient who visited his Martinsville, Virginia practice from the time of its opening in 2015 until a 2017 police raid, writing orders for more than 500,000 pills in less than two years.

In the 2019 case, the jury also found that Smithers caused the death of a West Virginia woman from the oxycodone and oxymorphone he prescribed.

Smithers, who did not take insurance, collected more than $700,000 in cash and credit card payments from patients who often traveled hundreds of miles to get there and then waited upward of 12 hours to see the doctor, according to the DEA.

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According to the agency, Smither's office lacked basic medical supplies, his receptionist lived out of a back room during the work week and many patients slept outside and urinated in the parking lot. 

Smither has been serving his sentence in a federal Atlanta prison.