Author: Cinthya Fillips, Director, Center for Alcohol and Drug Education Studies, Texas A&M Transportation Institute
Imagine this: over 20 million Americans hit the roads each year under the influence of alcohol or drugs. That’s 11% of everyone over 16, according to a groundbreaking study in Social Psychiatry and Psychiatric Epidemiology (Goings et al., 2023). These numbers are not just a statistic. It’s a wake-up call about the tangled web of impaired driving, mental health, and public safety. Let’s dive into this research, break down who’s behind the wheel, and explore what it means for our roads and communities.
The Study
Researchers Trenette Clark Goings, Christopher Salas-Wright, and Michael Vaughn investigated four years of data (2016-2019) from the National Survey on Drug Use and Health, analyzing 189,472 people. With 24,619 of whom admitted to driving under the influence (DUI) in the past year. Instead of lumping everyone into one bucket, the researchers used a method called Latent Class Analysis (LCA) to sort DUI offenders into distinct groups based on the substances they used: alcohol, cannabis, cocaine, heroin, hallucinogens, and methamphetamine. The result? A revealing typology that shows DUI isn’t a one-size-fits-all problem.
Four Faces of DUI
Here’s what they found: not all impaired drivers are the same. The study split them into four classes, each with its own story:
- Alcohol Only (55%): This is the biggest group with over half of DUI offenders. They stick to alcohol, averaging 7.73% of the general population in 2019. Picture older, often White, higher-income folks (think $75K+ households).
- Cannabis and Alcohol (36%): Next up, a younger crew (mostly under 35), with a diverse mix of racial backgrounds. All of them drive high on cannabis, and a third mix in alcohol. Cannabis DUI jumped from 4.28% to 4.96% over the study years.
- Polydrug (5%): Small but intense, this group consisted mostly of young men. This group is impaired by everything from cocaine to heroin to meth. One in five DUI offenders overall (20%) uses multiple substances.
- Methamphetamine (3%): The smallest slice, but don’t sleep on it. Nearly half of meth users (48.77%) drive under its influence, often from low-income rural areas (40% make under $20K). Meth DUI crept up from 0.24% to 0.38% in four years. Forming a quiet but rising threat.
Beyond the Wheel: Risk, Addiction, and Crime
These groups aren’t just categorized by what they use; they’re shaped by how they live. The Polydrug and Methamphetamine classes stand out as high-risk. Over 60% of Polydrug folks and 46% of Methamphetamine users love “dangerous thrills,” and about a third skip seatbelts, which signs to a broader disregard for safety. Drug ties run deep too: 28% of Polydrug and 26% of Methamphetamine offenders sell drugs, compared to just 1% in the Alcohol Only group.
Mental health is a glaring thread. The Methamphetamine class tops the charts with 66% battling illicit drug disorders (think meth or heroin addiction), while Polydrug users were at 46%. Cannabis/Alcohol folks show a 21% cannabis disorder rate, but Alcohol Only stays low at 1.5% for illicit drugs. Then there’s the justice system: 25% of Methamphetamine users faced arrests in the past year, and 22% were on probation or parole, rates that dwarf Alcohol Only’s 3% and 2%. These aren’t just traffic stops; they’re symptoms of bigger struggles.
Teens deserve a spotlight too. At ages 16 to 17, 74% of DUI offenders fall in the Cannabis/Alcohol class. Catch them early with mental health screening, and we might stop a lifetime of trouble, on the road and off.
Time to Act
Over 20 million impaired drivers demand action tailored to their profiles. One thing is clear: 11% of us are rolling the dice on our roads. With smarter enforcement, prevention, and support, we can lower that number—and save lives. Want to dig deeper? Check out Toward a typology of driving under the influence of alcohol and drugs in the Social Psychiatry and Psychiatric Epidemiology.
References:
Goings, T. C., Salas-Wright, C., & Vaughn, M. (2023). Toward a typology of driving under the influence of alcohol and drugs. Social Psychiatry and Psychiatric Epidemiology, 58(3), 227-238. https://doi.org/10.1007/s00127-022-02342-7
