Supreme Court THC Case Highlights Our Flawed Drug Laws

It was only a matter of time. It's not just our opioid laws that are a bona fide mess. Regulations regarding delta-9-tetrahydrocannabinol (THC), the primary active component of marijuana, are a chaotic patchwork of flawed, conflicting regulations, all but ensuring we'd face cases where the "science" is both contradictory and unfounded.

Perhaps nothing illustrates this better than the dysfunctional relationship between federal and state regulators regarding marijuana (cannabis). As of October 2024, 27 U.S. states and Washington, D.C. have decriminalized marijuana in some form, meaning that possession of small amounts of marijuana is treated as a civil infraction or a minor offense rather than a criminal one.

Yet, the DEA still (and ridiculously) classifies cannabis as a Schedule I (1) controlled substance, meaning that:

• It has a high potential for abuse.
• It has no currently accepted medical use in treatment in the U.S.
• There is a lack of accepted safety for its use under medical supervision.

I defy you to name a universe in which a coherent explanation exists for the diametrically opposed state and federal policies. 

Medical Marijuana vs. Horn goes to the Supreme Court

Largely due to the senseless nature of our marijuana regulations, the Supreme Court is now hearing the case of a truck driver, Douglas Horn, who is suing Medical Marijuana Inc. for selling a product called Dixie X, which the company advertised as "0% free  THC" CBD. Horn's wife purchased the product in 2012, hoping to control the severe pain following a trucking accident, but only after being reassured by the company that its claim was correct. It was anything but. The Horns, both truckers, were acutely aware that any indication of marijuana use would cost Mr. Horn his job. 

Shortly thereafter, Horn failed a random drug test due to the presence of THC, which led to his immediate termination. This was particularly distressing given his long career with no prior drug use or failed tests. Horn determined that the THC could have only come from the CBD, so he ordered a second bottle and sent it to a lab where THC was detected. The Horns then began legal action against the company, claiming that its mislabeled product cost him their livelihoods, and sought a significant settlement (2). 

The case before the Supreme Court is more subtle than the obvious disconnect between Federal and State laws, but in some ways, it is just as important. Why? At the heart of the case is the sticky problem of the detection of THC and the absence of any way to determine where the THC came from, when it was consumed, and whether it could have impaired his driving. 

Because of the high-stakes nature of the Horns’ occupation, federal law—and their employer— required the Horns to undergo random drug tests... Neither of the Horns had used marijuana in their adult lives

Medical Marijuana, Inc. v. Horn, currently before the U.S. Supreme Court under Docket No. 23-365.

The issue of THC-impaired driving is not new. In 2023, Dr. Henry Miller and I published a piece in the journal Law360 about the impossibility of 1) measuring THC and determining when it was consumed, 2) defining the blood levels of the drug that would represent impairment, and 3) determining whether any THC detected resulted from the use of marijuana or CBD oil. The latter is legal under the 2018 Farm Bill, provided that it is made from hemp and contains less than 0.3% THC.

Why marijuana science fails

There are several reasons why THC analysis fails to predict impaired driving. The first two are ACSH tenets.

1. The presence of a chemical or drug tells us nothing about the physiological response to that chemical or drug.
2. The dose makes the poison. With modern analytical techniques, it is now possible to measure chemical substances in concentrations as low as parts per billion or even parts per trillion. At such low levels, the chances of harm or impairment by any chemical or drug are essentially nil.
3. The pharmacokinetics of THC– it can persist in the body for as long as one month– make it impossible to determine when it was consumed, and how much was consumed.
4. There is no reliable standard concentration that defines impairment. In a 2023 paper published in JAMA Psychiatry, the authors write:

"[There] is as yet no scientific agreement on whether, and, if so, to what extent, these types of tests are indicative of marijuana intoxication

Marcotte, et. al.,  JAMA Psychiatry. 2023;80(9):914-923. doi:10.1001/jamapsychiatry.2023.2345

Bottom line

Although the flawed science used to regulate marijuana is not on trial,  Mr. Horn's predicament arises from these flaws. If he, needing relief from severe pain, ordered a faulty product, a company that set off a mostly meaningless test should be penalized. This is the problem with yes-no tests, which can only determine whether a particular instrument can detect a minute quantity of a drug that does or (probably) does not have any bearing on real life. One-size-fits-all laws typically fit none.

NOTES:

(1) The DEA is currently considering reclassifying THC (tetrahydrocannabinol), as a Schedule III substance under the Controlled Substances Act—big deal. The feds will still maintain that it is a controlled substance, requiring a prescription, while some states will allow it to be sold in stores. It still makes no sense.

(2) The Supreme Court is not debating the science of THC; the case before the Court involves whether Medical Marijuana can be treated as a RICO case.