Can Marijuana Use Cause Car Crashes?

by | Last updated Aug 11, 2022 | Published on Jul 8, 2022 | Cannabinoids | 0 comments


Marijuana is commonly found in the bloodstream of drivers involved in car accidents, including fatal ones. In fact, marijuana is only second to alcohol in this regard. As more states continue to legalize marijuana, it’s no surprise that the number of car crashes involving marijuana has increased exponentially. However, is marijuana directly responsible for causing more car crashes? The answer might not be so simple. 

Does Marijuana Lead to More Car Crashes?

A study looked at reports between 2000 and 2018 and found the percentage of car crash deaths in the United States involving marijuana doubled. However, the fatalities involving cannabis and alcohol have more than doubled. According to a study, at least 50% of people who died in crashes involving marijuana also had alcohol in their systems. 

The problem is that determining whether or not marijuana was the sole substance responsible for these crashes is difficult. This is so because THC – the active component in cannabis that makes you feel high – stays in the bloodstream for several days after ingestion. This means it’s impossible to determine if the drivers were feeling the effects of marijuana when they got in the accident. 

Not to mention, most people use marijuana and alcohol simultaneously. But, it’s challenging to separate the effects of alcohol and marijuana when someone is under the influence of both. Was it the alcohol or the marijuana that caused the accident? Another study suggests that reports aren’t consistent and haven’t been able to find a strong connection between marijuana use and car accidents. 

The Effects of Marijuana

When driving under the influence of alcohol or marijuana (or both), people tend to overestimate their ability and underestimate the risks they take while behind the wheel of their vehicle. Marijuana can make it harder to pay attention, focus, and react to things while driving. THC affects your brain in many ways that can impair your ability to drive safely, including:

  • Impaired judgment and driving skills
  • Slow reaction times
  • Altered perception of time and speed
  • Poor motor coordination
  • Cognitive impairment
  • Difficulty in problem-solving

Not surprisingly, people who drive while high on marijuana are more often involved in crashes than other drivers. In fact, according to a study by the National Highway Traffic Safety Administration (NHTSA), almost one in five (19%) drivers involved in fatal crashes had recently used marijuana, either alone or with alcohol. This was more than twice as many as those who had been drinking alcohol (8%).

One study found that if you’re only under the influence of marijuana, you might realize that your driving skills are impaired. This might lead you to use other strategies to make up for the fact that you’re high. However, if you’re under the influence of alcohol and marijuana, awareness and self-control are often impaired, leading to more dangerous decisions. 

Car Accidents in States That Have Legalized Marijuana

States that have legalized recreational marijuana use had higher rates of drivers testing positive for marijuana than states without similar laws. In comparison to neighboring control states, car crashes spiked 5 percent after the legalization of recreational marijuana in California, Colorado, Nevada, and Washington.

Despite those increases in crash rates, studies of whether marijuana makes drivers more likely to crash have been inconsistent. Most studies found no direct correlation between marijuana and car crashes, except when the drug is combined with alcohol. 

Considering that at least 11 percent of drinkers report using cannabis, and even 7.5 percent of occasional drinkers usually use cannabis with alcohol, it seems that the combination of these two substances is behind the rise in crashes. 

Using alcohol and marijuana together exacerbates the adverse effects of the substances. People who use both substances simultaneously are more likely to experience more negative side effects than those who only use alcohol. People who drink alcohol when they also use marijuana tend to drink more. 

Don’t Smoke and Drive

While marijuana use does not cause car crashes, it can impair driving abilities and increase the risk of a crash. This is why it’s important to remember: If you drive, don’t drive while using any drug or mind-altering substances.

Despite being legal for recreational use in many states, marijuana, and drug use while driving can still impair your ability to drive responsibly. Remember that driving under the influence of any kind of drug can be dangerous—even if you don’t believe it will significantly impact your driving ability. If you or someone close to you uses marijuana for medical or recreational purposes, please consider using alternative transportation when possible. 

Written by: Nick B.

Nicholas B. is the Corporate Director of Admissions for our substance abuse and behavioral health company. Nick’s mission is to provide quality care to every person that reaches out regarding substance abuse or behavioral health questions. Knowledge of an ever-changing industry, compassion when dealing with people, and compliance in every decision are the forces that drive his personal and professional growth.

Related Articles

Is Marijuana Stronger Now Than Ever Before?

Is Marijuana Stronger Now Than Ever Before?

For years there's been some fuss in the media about how marijuana, or "weed," produced today is way more potent than strains used in past decades. Is this true? If true, what could be the reasons for the increased potency? What are the health consequences of consuming...

Types of Synthetic Marijuana and Their Side Effects

Types of Synthetic Marijuana and Their Side Effects

If you've ever heard the term "synthetic marijuana," you've probably wondered what it was. Synthetic marijuana is a designer drug used by people who want to get high without getting caught by law enforcement. It comes in various forms, including liquid and powder, and...

A Life Free From Addiction Is Possible

Our admissions coordinators are available 24/7.
(888) 530-5023
Skip to content