John Grove stood out among the dozens of fatal drug overdose victims the Georgia Bureau of Investigation examined in November 2016.

It wasnt just the 34-year-olds hulking frame. At 6 feet 4 inches and nearly 270 pounds at autopsy, Groves muscular body showed few signs of the years hed spent battling opioid addiction.

But when his toxicology test came back in January 2017, it revealed something unusual. There were no opioids in his system, nor were there cocaine or benzodiazepines, which are now responsible for the overwhelming majority of drug overdoses. Instead, Grove tested positive for a single substance: mitragynine, best known as the psychoactive ingredient of kratom , an herbal drug derived from the leaves of a Southeast Asian tree related to coffee.

And it was mitragynine that had caused Grove to collapse on the floor of his coworkers bathroom and die, GBI concluded.

It was an odd and seemingly unprecedented determination. Scientists say theres scant evidence that mitragynine causes fatal overdoses , and many kratom advocates claim that overdosing on the substance alone is impossible. Although authorities have come forward with reports of deaths supposedly related to kratom, all of the cases theyve cited publicly have involved the presence of other, often more dangerous drugs, making it nearly impossible to discern kratoms role in the fatalities.

But mitragynine was the only substance on Groves toxicology test. His death, listed as an acute mitragynine intoxication, could have provided an important window into how this drug supposedly kills humans when taken in isolation.

HuffPost took a closer look at Groves case and other kratom-related deaths in Georgia. We found that not only is the state using sloppy reporting on these deaths, likely overestimating the apparent harms of kratom, but the state also appears to be rushing to blame mitragynine for the deaths of people like Grove, even when there may be more likely culprits.