Stoned Driving: Marijuana DUIs Leave Lawmakers Dazed & Confused

The legal issues surrounding marijuana laws, driving, and car insurance are enough to leave you dazed and confused.

marijuana leaf dui stop sign

America's history with marijuana is lengthy and fraught with hiccups. After decades of prohibition, the doorway of decriminalization paved the path for legal pot.

Weed is legal for recreational use in eight states plus DC. 20 states allow medical marijuana, and most of the remaining states decriminalized the drug. More states are currently pushing for full legalization.

The change in legality has led to some growing pains for lawmakers and police. Chief among them is how to handle stoned drivers. Many current testing methods have inherent flaws. Accurately diagnosing and prosecuting drivers impaired by pot is a challenge.

Legal cannabis is slowly becoming common. But it's still illegal at the federal level. The lack of standards and peer-reviewed studies makes pioneering states testing grounds for legal weed.

Current Climate of Cannabis and Cars

As legalization picks up steam across multiple states, studies and stats trickle in. Here are key findings:

  • Pew Research survey reveals that 57 percent of Americans currently support legalization. That's a huge leap from 16 percent in 1990. This gap that will increase.
  • Columbia University found that drunk drivers are 16 times more likely to get in a fatal accident than drivers who test positive for pot.
  • Center for Disease Control says that marijuana users are 25 percent more likely to get in an accident. They stress that factors like age and gender may play a role in higher crash rates.
  • Insurance Institute for Highway Safety says collision claim frequency in Colorado, Washington, and Oregon rose by three percent. They say that recreational cannabis is the main culprit behind the increase.
  • American Journal of Public Health, on the other hand, found no increase in fatality or crash rates in Colorado and Washington.

It's difficult to draw conclusions about the affects of legalization. More studies will paint a clearer picture as recreational cannabis reaches more states. Some current findings seem to contradict each other, perhaps due to study controls and conclusions.

It's also not yet clear how weed impacts motor skills. When trying to decide if they're too high on marijuana to drive, many pot users actually overestimate how impaired they are. This is a key difference from alcohol, where drunk drivers tend to underestimate their intoxication level. Also, The NCBI found that “most marijuana-intoxicated drivers show modest impairments on actual road tests." A driving simulation by the NIDA shows that stoned drivers suffer slight cognitive difficulties.

Law enforcement, as a result, struggle with accurately testing and applying laws to reefer users. It’s a double faceted problem: we don't have proper drug testing methods largely because we don't completely understand cannabis. It's no surprise that many current cannabis DUI testing methods are under fire.

Today, states use two approaches to test stoned drivers: per se or effect-based laws. Both tests face criticism. "Neither type of test is accurate because neither is validated to detect marijuana impairment," says Jolene Forman, staff attorney with the Drug Policy Alliance.

Per Se DUI laws lack science

Per se laws, or THC threshold tests, are controversial. They set a limit for how much cannabis can be in a person's system while driving. If tests find a specific trace amount of THC in the driver, they are deemed impaired.

Contrary to other tests, per se DUIs do not require any signs of impairment. And the science behind them is contentious.

"THC threshold tests only measure, at best, whether a person has consumed marijuana at some point in the past few days," says Forman. Many others share her opinion.

"Such laws are generally unpopular because science has not validated the presence of specific thresholds of substances other than alcohol as predictors of driver impairment," says Paul Armentano, NORML's deputy director. NORML is an advocacy group focused on drug law reform.

Failing a per se sobriety test doesn't guarantee that a driver is high. Most states with per se DUI laws have set the limit at five nanograms of THC per milliliter of blood. Critics of the laws claim that limit is arbitrary. They also contend that THC measurements are inherently inaccurate.

The National Highway Traffic Safety Administration agrees. "It is difficult to establish a relationship between a person's THC blood or plasma concentration and performance impairing effects," their study concludes. "It is inadvisable to try and predict effects based on blood THC concentrations alone."

People metabolize marijuana and alcohol differently. Daily pot users will have THC in their blood long after use. They can fail a per se DUI test without recently using cannabis. Cases where a sober driver gets a drug driving charge are already happening in per se states.

"Marijuana may be detected hours, days, or even weeks after use, long after any possible impairment has dissipated," says Forman. "This would be equivalent to a test showing that a person had a glass of wine or some beer nights or even weeks prior. It would tell you very little about whether the person is presently impaired," she concludes.

"[Users] can test positive for four days for infrequent users, and up to ten days for daily users," says Ravi Spaarenberg, CEO of Sensi Seeds. "This clearly does not provide a conclusive answer to the question if the person was in fact under the influence of cannabis while driving."

Here are the biggest criticisms of per se pot laws:

  • Not scientifically sound. There aren't widely accepted levels of impairment for cannabis like alcohol. Heavy users can have illegal amounts of THC in their system without using any pot.
  • Doesn't account for tolerance. Five nanograms of THC, the legal limit, impacts people differently.
  • No consensus. There are various sobriety tests like hair, urine, or blood analysis. Each tests may analyze different cannabis compounds, and they can contradict one another. Standardized tests backed by science are necessary.
  • Risk of false positives. Equipment and technology to determine intoxication aren't foolproof.

Disputing effect-based DUI laws

Some states forego THC threshold tests in favor of effect-based tests. This requires evidence of impaired driving. Courts must also prove that impaired performance was due to cannabis. Like per se laws, effect-based laws come with their fair share of criticism and debate.

When a cop pulls over a suspected drunk driver, they look for visual clues. Slurred speech, bloodshot eyes, decreased motor skills, and the smell of alcohol are some indicators. With the exception of red eyes and a potential smell, stoned drivers don't give off such clues.

"When law enforcement stop a vehicle and interact with the driver, it is often very difficult to tell if a person is under the influence of marijuana," says attorney Matt Pinsker.

Even with obvious signs of impaired driving, it's not easy to tie it weed. Law enforcement don't have standardized THC test kits and detection techniques. This is partly due to the recency of legalization.

"There are a host of problems with drug testing techniques and analyses, including the substantial risk of false positive test results, false negative test results, specimen contamination; and chain of custody, storage, and re-testing issues," says Forman.

"THC tests are unreliable and often incorrect," she continues. "Chemical testing, like many other forensic disciplines, is highly technical and imperfect."

The discrepancies with these tests make prosecuting pot DUIs a challenge.

Courts struggle to convict users

Changing sobriety standards, no caselaw to reference, and unreliable test methods make prosecuting pot DUIs a challenge.

"Cases are more complicated to prosecute and take considerably longer than a classic drunk driving case," says attorney Todd Spodek. Courts across the country have trouble proving that stoned drivers are too stoned to drive.

There are several examples of overturned marijuana DUI charges:

  • Unscientific nanogram limits: Several drivers have successfully argued that their DUIs were based on inaccurate nanogram levels.
  • Faulty impairment recognition: One officer in Georgia made over 90 DUI arrests in 2016. Judges dismissed many charges after further testing invalidated his findings.
  • Medical exceptions: Drivers with medical marijuana authorizations get extra leeway in some states.
  • Improper testing: Some police use inappropriate methods to entice a confession. Without proof of impairment, that confession is less convincing.

Why is it so difficult to properly identify stoned drivers?

We're still learning the science behind the psychoactive properties of pot. According to the NCPIP, there are more than 480 natural components in cannabis, 66 of which are unique chemicals known as cannabinoids. They're divided into the following subclasses:

  • Cannabigerols (CBG)
  • Cannabichromenes (CBC)
  • Cannabidiols (CBD)
  • Tetrahydrocannabinols (THC)
  • Cannabinol (CBN) and cannabinodiol (CBDL)
  • Other cannabinoids (such as cannabicyclol (CBL), cannabielsoin (CBE), and cannabitriol (CBT)

Studies have found that the cannabinoid most responsible for making users feel 'high' is THC. THC is fat-soluble while alcohol is water-soluble. This means that THC takes much longer to breakdown. Essentially, THC stores itself in your fat cells while alcohol dissolves quickly through your liver.

Failing an alcohol breathalyzer means alcohol is active in your system. But finding THC in your bloodstream doesn't mean said THC is active.

THC metabolizes into two main forms: 11-OH-THC, or hydroxy-THC and THC-COOH, or carboxy-THC. THC-COOH, unlike THC, is not psychoactive. Conversely, 11-OH-THC, the active metabolite of THC, has psychoactive properties.

A urine test may reveal THC-COOH in the system, but that doesn't prove that 11-OH-THC is present. Drug tests that look for THC-COOH, therefore, aren't conclusive in determining impairment.

THC-COOH is easier to detect for a longer period. Some lawmakers don't understand the nuances of THC, thus many sobriety tests look for any form of THC. And tests become even murkier when factoring varying levels of tolerance or ingestion methods.

We need more studies to fully understand the science of how we ingest marijuana and how it impacts driving. That's why many people advocate for new approaches to testing stoned drivers.

Improving Marijuana DUI Laws

It's clear that current approaches to determining cannabis intoxication fall short. The lack of conclusive tests make prosecuting stoned drivers a challenge.

"These tests are so unscientific that they both under and over punish drivers," says Forman. She states that, due to testing and prosecuting inconsistencies, innocent drivers can be incorrectly punished. Similarly, actual stoned drivers may beat sobriety tests or have their cases dropped.

What can lawmakers do to improve marijuana DUI tests? For starters:

  • Improve technology: Current testing methods aren't foolproof. Authorities should study and invest in new tech. Several startups hope to develop better methods, but their efficacy isn't yet known.
  • Better training: Law enforcement must work to better recognize symptoms of reefer impairment. New equipment should also be incorporated.
  • Understanding cannabis: More marijuana studies are absolutely necessary. Since the plant is illegal on a federal level, research grants and funding is hard to come by. As legalization becomes common, more studies will unearth new findings.

Marijuana DUI Statistics

There are some studies on stoned driving in legal states. These are their findings:

  • Washington Traffic Safety Commission: Studied toxicology reports from 1,773 fatal accidents between 2010 and 2014.
    • 60 percent of drivers tested positive for alcohol, pot, or other drugs.
    • Eight percent of drivers tested positively for only marijuana.
    • In 2014, 84 percent of pot-positive drivers had hydroxy-THC in their system. Of those, about half exceeded the five nanogram legal limit.
    • THC positive drivers were involved in more daytime crashes. Alcohol accidents, on the other hand, frequently occurred in the night.
  • Council on Responsible Cannabis Regulation: Examined data from the Colorado Department of Transportation.
    • Less than eight percent of DUI citations involved solely weed.
    • 12.3 percent of all drivers in fatal crashes tested positive for cannabis. 32.7 percent tested positive for alcohol.
    • Total number of cannabis DUIs decreased by 1.3 percent from 2014 to 2015.

These are some of the first marijuana DUI statistics and studies. In reality, there isn't much concrete information yet. It's difficult to make definitive statements about the impacts of pot after only a few years of legality. Time will reveal more trends and correlations.

What to do if Arrested for Marijuana DUI

Without an accurate measure of THC levels, drivers must simply drive when they feel sober. So, police are more conscious of stoned drivers, and they charge more drivers with marijuana DUIs.

If you are pulled over and arrested for driving high, you automatically consent to take a blood test. You do have the option to refuse the blood test. This requires a hearing with the department of licensing that can result in a long license suspension. Some attorneys recommend taking the blood test, as murky weed DUI laws could work in your favor:

“There is little case law on the admissibility of marijuana chemical tests in New York. Therefore the statute would guide that if a driver consented to a test, there is a strong case for admissibility” says Kimberly Anne Palesz Defense and Family Law.

A good lawyer can question the process leading to a DUI arrest, including poking holes in the testing process. As we know, today's testing methods aren't reliable.

"Although Field Sobriety Tests can be somewhat reliable for marijuana, unlike the breath test in the field for alcohol, there is no scientific instrument which measures levels of THC in the field," says Pinsker.

Just because you’ve been arrested for a pot DUI doesn’t mean you can’t save money on car insurance. Compare quotes from multiple companies and lower your insurance rates.

Fighting a Marijuana DUI

Regardless of the specifics of your case, hiring a competent DUI lawyer is a must. They give you a much higher chance of getting a good case result. Not only that, but our research shows that DUI lawyers are always worth the cost.

The newly imposed laws give authorities more ground to charge you with a DUI. That said, you’re also more likely to beat the DUI charge. Lawyers can question the legitimacy of the blood test to see if officers use proper procedure. In most states, only a few labs have approval for blood tests.

“DUI Marijuana cases are much easier to defend. If an attorney knows the science behind the chemical testing, DUI marijuana is typically one of the easiest cases to win,” says criminal attorney Michael A. Dye.

In states that don’t have a legal limit, it’s even easier to prove your innocence in court.

"It’s not enough to merely suspect someone has consumed marijuana. In the absence of an admission or a blood test, it can be very difficult if not impossible to prove that this person has used marijuana," says criminal defense attorney Glenn Kurtzrock.

Even with a positive test, authorities must prove that poor driving is due to intoxication. This has led to some novel and interesting cases by defendants in cannabis DUI cases.

“One position that many defendants take is to state they are frequent users of marijuana, therefore even if they test above 5 nanograms of active THC they are still not impaired,” says Lindsey Parlin a Colorado attorney.

What Happens if Convicted of a Marijuana DUI

Weed-related driving laws in many states are ambiguous. This can give you an advantage in court. However, there is still a very real chance you will be convicted of a pot DUI.

A pot DUI carries the same criminal punishment as an alcohol-related DUI. But it can result in greater fines and jail time due to marijuana’s drug classification.

While legal in some states, the DEA still classifies reefer as a Schedule 1 drug. Marijuana DUI penalties can lead to greater fines or jail time depending on the offense.

Aside from fines and jail time, the state can suspend your license. After license suspension, the state notifies your insurer. This will impact your policy in a negative way.

Insurers will likely classify you as a high-risk driver. This increases your car insurance premiums for up to seven years. Depending on your driving history, your insurer could cancel your policy.

In some states, you may need to file for an SR-22. An SR-22 proves that you have purchased the state minimum amount of coverage. Don’t let a weed DUI force you to overpay for car insurance.

DUI’s are expensive. The whole process on average costs $10,000 and another $5,000 in car insurance rate increases! If you get a pot DUI, it pays to compare quotes from other companies. Your current insurer may no longer offer you good deals, but there may be companies that have better rates for you.

The Future of High Driving

There's a gold rush to come up with a scientifically sound pot sobriety test. From experimental breathalyzers to sobriety test apps and saliva swabs, the race is on.

"Unfortunately, no one has come close to perfecting the technology for an accurate cannabis breathalyzer," says Rebecca Gasca, CEO of Pistil and Stigma.

Advocates stress that there's no golden goose for cannabis detection. A sound detection policy needs a bottom-up approach with several different recognition methods.

"These include greater use of drug recognition evaluators, the use of modified roadside field sobriety tests, the provisional use of use of roadside cannabis-sensitive detection technology, such as saliva test or breath test, and the provisional use of handheld performance technology," says Armentano.

As more and more states open the door to recreational pot, we will learn more about cannabis and driving. The pioneer states are crucial in guiding the conversation to form sensible policy for dealing with stoned drivers.

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