(Stacker) – Delayed packages, bare grocery store shelves, and inflated prices have become the norm for American consumers over the past two years. While the COVID-19 pandemic has been the catalyst, there are other challenges causing supply chain issues, including a lack of truck drivers to transport goods from one place to another. In late 2021, the American Trucking Associations reported that the driver shortage had risen to an all-time high of 80,000, partly due to the aging population and shrinking wages.

In response, the Biden administration vowed in December to get more truck drivers on the road by boosting recruitment efforts and expediting the issuing of commercial licenses. However, that won’t have an effect on another hurdle: disparate marijuana laws across the U.S. that are contributing to an increase in violations. In 2022, a growing number of truckers are being taken off the job, which could soon worsen the already suffering supply chain.

As more states legalize recreational marijuana—four of which did so in the past year and three more are expected to by the end of 2022—more truck drivers have tested positive for the substance. As of April 1, 2022, 10,276 commercial vehicle drivers have tested positive for marijuana use. By the same time in 2021, there had been 7,750 violations. That’s a 32.6% increase year over year.

Truck drivers who travel cross-country face inconsistent state regulations as 19 states have legalized recreational marijuana and 37 states permit it for medicinal purposes. But even if a driver used marijuana or hemp-based products like CBD while off duty in a state where those substances are legal, they could still be faced with a violation due to the Department of Transportation’s (DOT) zero-tolerance policy at the federal level. “While states may allow medical use of marijuana, federal laws and policy do not recognize any legitimate medical use of marijuana,” a DOT handbook for commercial vehicle drivers reads. “Even if a state allows the use of marijuana, DOT regulations treat its use as the same as the use of any other illicit drug.”

Stacker looked at what’s causing thousands of truckers to be removed from their jobs, and the looming domino effect of the continued supply chain disruptions.

Truck drivers are being tested more and the consequences for drug-related violations have increased

Under regulations set forth by the DOT, truck drivers are tested for drug use—including marijuana—prior to starting a new job. They can also be tested at random, as well as after accidents. In January 2020, the DOT’s Federal Motor Carrier Safety Administration also upped the random drug testing rate from 25% of the average number of driver positions to 50%. Truck drivers are mainly screened for drug use via urinalysis, but there are now new saliva tests being proposed as well.

At worst, if a driver fails just one drug test, that can be grounds for termination under DOT regulations. At best, they are temporarily taken off the road and required to complete an evaluation with a substance misuse professional who determines their rehabilitation process, which can sometimes take months.

As of January 2020, employers are also required to list commercial drivers who fail a drug test in the FMCSA’s Drug & Alcohol Clearinghouse. These violations remain searchable for five years. Potential employers are also required to check the Clearinghouse to see if a commercial driver had any previous violations, which would prevent them from being hired.

Differing marijuana laws by state are causing confusion among truck drivers

In recent years, more states have legalized both recreational and medical marijuana, making it more widely available and used. However, marijuana use is still prohibited for commercial truck drivers, state laws and medical prescriptions aside. According to the FMCSA, “a driver may not use marijuana even if [it] is recommended by a licensed medical practitioner.” The DOT has maintained its zero-tolerance stance for marijuana use even as it’s become legalized, saying, “Legalization of marijuana use by States and other jurisdictions also has not modified the application of U.S. Department of Transportation drug testing regulations.”

A commercial driver could use marijuana while off-duty, not driving, and in a state where marijuana is legal, but still test positive for the substance for up to a month later and be taken off the road. The American Addiction Centers says for infrequent marijuana users—meaning those who use the substance less than two times a week—it can show up in their urine for up to three days. Someone who uses marijuana several times a week can test positive for up to three weeks, and those who use marijuana even more frequently can “test positive for a month or longer.”

Truck drivers with violations tend to not return, adding to the shortage and supply chain woes

Shortages, factory closures, and goods waiting to be unloaded at ports are just some of the current issues affecting the supply chain across America. Trucking transports 72% of products within the U.S., according to a report from the White House, but a growing number of commercial drivers are sidelined for marijuana use.

The return-to-duty process that commercial vehicle drivers must undergo once faced with a marijuana violation can keep them from returning to work at all. According to the FMCSA’s monthly report, 89,650 commercial drivers are currently in prohibited status as of April 1, 2022, but 67,368 of them have not begun the RTD process. 

If violations continue at the current rate, the truck driver shortage will further disrupt the supply chain, which means higher prices not just for commodities but the cost of living at large.