Why Cannabis Research Is Still Limited

Cannabis is one of the most talked-about substances today, but the science behind it is not as strong as many people think — and that’s a key reason DOT regulations remain strict. There are two main causes for this gap. First, cannabis is still classified as a Schedule I controlled substance in the United States, the same category as heroin. This makes it extremely difficult for researchers to get approval and funding for studies. Second, cannabis is not a single chemical. It is a complex plant with hundreds of compounds, and each one may affect the body differently. Studying its effects is like trying to understand an orchestra by isolating each instrument — complicated and slow. Because of these limits, we still don’t have enough large-scale, long-term evidence to fully understand cannabis’s risks or benefits. For jobs where public safety is on the line, this uncertainty means regulators cannot afford to take chances.

The Reality Check: Because research is limited and inconsistent, DOT keeps a strict stance to protect safety in transportation.