As more states legalize cannabis, policymakers, law enforcement agencies, and public safety professionals continue to ask an important question: How does legalization affect impaired driving? A recent doctoral study exploring the perspectives of Maryland Drug Recognition Experts (DREs) offers valuable insight into what officers are experiencing on the front lines.
Cannabis Legalization and Roadway Safety
Maryland legalized adult-use cannabis on July 1, 2023, following the passage of the Cannabis Reform Act. While the law allows adults 21 and older to possess and use cannabis under specific conditions, concerns remain about its impact on roadway safety and impaired driving.
To better understand these impacts, Raymond D. Brooks conducted a qualitative study interviewing eight certified Drug Recognition Experts from across Maryland. These officers, specially trained to identify drug impairment, shared their experiences with cannabis use, driving behavior, enforcement challenges, and public perceptions since legalization.
Four Major Themes Emerged
The study identified four consistent themes among participating DREs:
- Increased availability of cannabis
- Greater prevalence of use and changing public perceptions
- Shifts in law enforcement training and enforcement practices
- A need for expanded education and outreach efforts
Let’s take a closer look at each.
1. Cannabis Is More Available Than Ever
Most participants reported a noticeable increase in cannabis availability following legalization. Officers cited the rapid growth of dispensaries, easier access for adults, and greater visibility of cannabis use in public settings.
Several DREs also reported encountering more cannabis odor during traffic stops and routine interactions. One participant noted that dispensaries are now common throughout their jurisdiction, making access easier than before legalization.
The study found that increased availability was one of the most significant changes observed by officers statewide.
2. Public Perception Has Shifted
Participants consistently described a growing perception among cannabis users that consumption is socially acceptable and carries fewer risks than other impairing substances.
Many officers reported encountering drivers who believed cannabis actually improved their driving abilities. DREs expressed concern that some users equate legalization with safety, despite evidence that THC can impair attention, reaction time, and decision-making skills.
According to the study, officers observed:
- Increased cannabis use among drivers
- More cannabis-related paraphernalia in vehicles
- Greater acceptance of cannabis consumption in everyday settings
- A belief among some users that driving after cannabis use is less dangerous than driving after drinking alcohol
These findings suggest that legalization may be influencing attitudes as much as behavior.
3. Law Enforcement Is Adapting
All participants reported receiving some form of training related to cannabis legalization. Much of this training focused on policy changes, charging procedures, legal updates, and search-and-seizure requirements.
Officers also identified increased interest in programs such as:
- Advanced Roadside Impaired Driving Enforcement (ARIDE)
- Drug Recognition Expert (DRE) certification
- Cannabis impairment detection courses
- “Green Lab” training, where officers observe individuals before and after cannabis consumption in controlled environments
However, participants noted that advanced training is often voluntary rather than mandatory. Some officers also expressed hesitation about pursuing cannabis-impaired driving cases because of the complexity and time required for investigations.
4. Education May Be the Missing Piece
Perhaps the strongest consensus among participants was the need for more education.
DREs recommended broader public awareness campaigns focused on the risks of driving after cannabis use. They also advocated for additional training for law enforcement officers, prosecutors, judges, and policymakers.
Participants emphasized that many members of the public do not fully understand how cannabis affects driving performance. Several suggested incorporating cannabis-impaired driving education into driver licensing programs and community outreach initiatives.
The study concludes that education could play a critical role in reducing impaired driving and helping communities navigate the realities of cannabis legalization.
Key Takeaways
The research does not conclude that legalization directly causes more impaired driving arrests. Instead, it highlights the experiences and observations of Maryland’s Drug Recognition Experts during the first years following legalization.
Their perspectives paint a consistent picture:
- Cannabis is more easily accessible.
- Officers are encountering cannabis use more frequently.
- Many drivers underestimate the risks of driving while impaired by cannabis.
- Agencies are adapting through training, but gaps remain.
- Public education is viewed as essential for improving safety.
Looking Ahead
As cannabis legalization continues to expand across the United States, Maryland’s experience offers valuable lessons for transportation professionals, policymakers, law enforcement agencies, and traffic safety advocates. The findings suggest that legalization is not simply a legislative change. It also influences public perceptions, enforcement practices, and roadway safety considerations that require continual monitoring and education.
Source:
Drug Recognition Experts’ Perspectives on the State of Maryland’s Legalization of Cannabis and Its Impact on Impaired Driving by Raymond D. Brooks, Walden University (2025).
