A Tennessee appeals court has upheld the reinstatement of a longtime sheriff’s deputy who was fired after testing positive for THC, finding there was sufficient evidence to support the conclusion that legally purchased CBD gummies could have caused the positive result.
In a September 21 ruling, the Tennessee Court of Appeals affirmed a decision overturning the termination of David McGriff, a deputy with the Shelby County Sheriff’s Office since 2005.
McGriff was ordered to undergo a random drug screening in April 2024. His urine sample tested positive for THC, and a subsequent hair sample tested positive for cannabinoids, specifically carboxy-THC. The sheriff’s office terminated him in July 2024 following an internal investigation.
McGriff appealed to the Shelby County Civil Service Merit Board, telling the board that he had not used illegal marijuana and that the THC instead came from legally purchased CBD gummies he occasionally took at night for stress and sleeplessness.
The board reversed his termination, and Shelby County challenged that decision in court.
Central to the case was whether a positive THC result established that McGriff had unlawfully consumed marijuana.
The sheriff’s drug-free workplace policy prohibited the “unlawful use of illegal drugs,” but testimony presented to the board established that legally sold CBD products could contain THC and that the testing performed on McGriff could not determine where the THC originated.
A registered nurse who oversaw drug screening services for the sheriff’s office acknowledged that THC could enter a person’s system through CBD products and that a positive test could not distinguish between illegal marijuana consumption and legal CBD use.
A board-certified pathologist provided similar testimony, explaining that CBD use could result in a positive THC test and that variables including product potency, frequency of use and method of consumption could affect the results.
The pathologist concluded that the testing documents could not establish whether McGriff’s THC result was caused by marijuana or CBD.
The appeals court said there was no meaningful dispute that, under the laws considered during the administrative proceedings, legally purchasable CBD products could contain some THC. The court also noted that witnesses agreed the drug tests could not establish the source of the THC detected in McGriff’s samples.
McGriff testified that he had undergone at least 25 random drug tests during his career without previously testing positive. He also denied ever being under the influence while working.
The Civil Service Merit Board credited McGriff’s explanation, and the appeals court said courts must generally defer to such credibility determinations when supported by the record.
“Substantial and material evidence” supported the board’s finding that McGriff had not violated the sheriff’s drug-free workplace policy prohibiting unlawful use of illegal drugs, the court concluded.
The board did find that McGriff violated a separate narcotics rule because he reported for duty with THC in his system, but it determined that violation did not provide just cause for termination.
A Shelby County chancery court previously upheld the reinstatement, at one point describing the sheriff’s drug-testing policy as “out of step with current law and science.”
The Court of Appeals agreed that reinstatement was justified, rejecting the county’s argument that the board acted arbitrarily or without sufficient evidence.
The appeals court did, however, overturn the lower court’s decision establishing December 15, 2024 as the date from which McGriff should receive pay. The court found that the Merit Board had not clearly established a return-to-work date and sent that issue back to the board for further consideration.
The ruling does not establish that every positive THC test can be attributed to legal CBD use. Instead, the court found that, based on the evidence in McGriff’s case, the sheriff’s office had not established that the detected THC resulted from unlawful drug use.
