Marijuana Laws and Driving in Washington and Colorado

Marijuana Laws and Driving in Washington and Colorado

Sorting Out DUI and Safety for Pot-Using Motorists


Soon after voters in Washington state passed Initiative 502 in November 2012, legalizing private recreational marijuana use by adults, smokers gathered at the Space Needle in Seattle to celebrate. Law enforcement officers indulged them, overlooking for an evening the fact that the law does not allow public consumption.

Now the party's over, and legislators and others in Washington and Colorado, which passed a similar measure, are grappling with a number of legalization issues, including how to handle people who use marijuana and then drive.

If you live in Colorado or Washington, or plan to travel there, here's an update on how the new marijuana laws affect driving now and how the impact of legalized pot may play out.

Decisions that officials make in Colorado and Washington are likely being watched in many other states that are debating whether to legalize the use of non-medical marijuana.

Two States, Two Different Laws
Washington and Colorado handled the legalization differently when it comes to marijuana use by drivers.

Washington state has defined a standard for how much of marijuana's active ingredient, tetrahydrocannabinol or THC, must be in the bloodstream before a driver can be charged with driving under the influence (DUI).

Under the new law, it is not lawful to operate a motor vehicle with a level of 5 nanograms per milliliter of THC in the blood, as detected by a blood draw.

If a driver has a level of 5 nanograms THC or greater, he or she will face the same conviction as a driver under the influence of alcohol or other drugs.

For a first offense, punishment includes suspension of the license for 90 days (even before conviction) and fines, which vary by court, says Brad Benfield, a spokesman for the Washington Department of Licensing.

If a driver is convicted, that license suspension could extend to up to four years. Conditions to get it back vary, possibly including drug rehab classes, court fines and licensing reissue fees.

"It does set a legal standard of intoxication [with marijuana] where one didn't exist before," Benfield says of the new law.

Colorado's Amendment 64, also passed in November 2012, legalizes private pot use by most adults and allows them to grow a small number of marijuana plants. However, no legal blood limit was set for drivers. The debate about what should be done is ongoing.

In one of the latest drafts in Colorado, legislators are recommending that drivers who test over the legal THC limit could argue they were not impaired.

The same provision does not exist in state law that's applied to those charged with being under the influence of alcohol. If they have a blood alcohol level of .08 or higher, they are automatically considered impaired.

"The ability to drive does not play in'' when a driver is suspected of driving under the influence of alcohol, says Jared Adams, a Denver attorney.

The new proposal, which requires an evaluation based not just on blood levels but impairment linked with marijuana, will be introduced in the 2013 legislative session, Adams and others predict.

Comparing Alcohol and Marijuana
The effects of alcohol can't be compared, apples to apples, with the effects of marijuana, says Lenny Frieling, an attorney and chairman of the Colorado chapter of the National Organization for the Reform of Marijuana Laws (NORML).

"Unlike alcohol, the correlation between active THC in your blood and impairment in driving is poorly correlated," he says.

Paul Armentano, deputy director of NORML nationally, agrees. "There is much greater variability about how marijuana influences behavior [compared to alcohol]," he says. The same amount of marijuana, for instance, may greatly affect a new smoker but not an experienced or chronic smoker, Armentano says.

Body weight can play a role, too, in one's reaction, he says.

Maximum blood levels of THC occur before the onset of impairment, he says. "As the levels go down, impairment goes up."

"The body processes marijuana in a fundamentally different manner than it does alcohol," Armentano says. For that reason, blood tests for marijuana are not impairment tests, he says, but simply detection tests that don't reflect the degree of impairment.

More study is needed, he says, to figure out how to gauge if someone's driving is affected by his marijuana use. It's a matter of identifying the best tests to detect actual impairment from marijuana use, he says.

While the effect of marijuana are variable, he says, "generally users perform most poorly 20 to 40 minutes after inhalation, but after 60 minutes their performance often begins to return to what it was before smoking."

Having a medical marijuana prescription has no impact on whether a driver will get a DUI, Frieling says, although many motorists think otherwise. If they are under the influence, they will likely be charged, he says.

Research on Alcohol, Marijuana and Driving
Marijuana and alcohol do affect drivers differently, as Armentano says and several medical studies suggest.

In one study, published in 2009, Yale researchers looked at the effects of marijuana and alcohol on the ability to drive, reviewing published studies.

Both substances impaired driving skills, they found. However, they found that the effects of marijuana varied more greatly among people than did alcohol effects.

They also found that marijuana smokers tend to compensate while driving by a variety of strategies, such as driving more slowly or passing less often.

However, combining alcohol with marijuana eliminates the ability to use the strategies, they found.

In a more recent study, published in 2012 in the journal Clinical Chemistry, researchers who reviewed published evidence found that blood THC concentrations of 2-5 nanograms per milliliter ''are associated with substantial driving impairment, particularly in occasional smokers."

They found that higher blood THC concentration is linked with increased crash risk, although other experts disagree. But studies don't show a direct correlation between impaired driving and THC concentration, the researchers say.

Combining alcohol and marijuana definitely increases the risk of crashes, experts say.

Advice for Drivers
Whether you are trying to avoid drivers who are under the influence of marijuana or trying to avoid your own legal problems, knowing a ''safe'' interval between smoking and driving is wise.

However, there's no agreement on what that interval is.

The National Highway Traffic Safety Administration, on its Web site, states: "Marijuana has been shown to impair performance on driving simulator tasks and on open and closed driving courses for up to approximately 3 hours."

Among the impairments are worse car handling, increased reaction times, impaired estimates of distance, sleepiness, lack of coordination and less vigilance, NHTSA says.

Other expert sources say that 3 hours is not nearly enough time to wait before driving.

Steve Graham, an attorney in Spokane and a former prosecutor, has counseled medical marijuana users.

"After smoking they need to wait until they are clear-headed enough," he says. "My advice would be [to wait] for 10 hours, particularly for frequent users. If in doubt, you really need to stay off the road."

Advice about a ''safe'' time interval also hinges, experts say, on whether the person is a new user or a veteran. Novices will likely be affected more strongly. The potency of the marijuana also affects its impact.

Frieling, the Colorado attorney and state NORML chairman, says the 3 hours suggested by NHTSA seems conservative.

"I tell [users] an absolute minimum of 3 hours, and that that isn't a safe number but it may be a practical number. A small number of people will have a THC level of 5 and over after [that window]."

It's hard to advise a set time, says Adams, the Denver attorney. The best advice, in his opinion: Get a good night's sleep before driving again, "and be very careful."

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  • oldefarte oldefarte Posts:

    A 5 nanogram limit? A regular smoker will keep that much in their system. For example: in the U.S.Army during the 1980s, a 4 nanogram level was established as a basis for throwing someone out of the service. One only needs to smoke marijuana a few times in a weekend in order to have 5ng on a Monday morning drive to work. The THC metabolite that is being measured will stay in the body for quite some time if the individual is a regular smoker. Even someone doing just a few joints during a weekend will still test at above the 5ng level for up to 30 days after they stop.

  • krymsun krymsun Posts:

    A 2002 review of seven separate crash culpability studies involving 7,934 drivers reported, “Crash culpability studies [which attempt to correlate the responsibility of a driver for an accident to his or her consumption of a drug and the level of drug compound in his or her system] have failed to demonstrate that drivers with cannabinoids in the blood are significantly more likely than drug-free drivers to be culpable in road crashes.” [Chesher et al. Cannabis and alcohol in motor vehicle accidents. In: Grotenhermen and Russo (Eds) Cannabis and Cannabinoids: Pharmacology, Toxicology, and Therapeutic Potential. New York: Haworth Press. 2002: 313-323.] But, unlike with alcohol, the accident risk caused by cannabis, particularly among those who are not acutely intoxicated, appears limited because subjects under its influence are generally aware of their impairment and compensate to some extent, such as by slowing down and by focusing their attention when they know a response will be required. [Allison Smiley. Marijuana: On-Road and Driving Simulator Studies] This response is the opposite of that exhibited by drivers under the influence of alcohol, who tend to drive in a more risky manner proportional to their intoxication.[United Kingdom's Advisory Council on the Misuse of Drugs. The Classification of Cannabis Under the Misuse of Drugs Act of 1971. 2002: See specifically: Chapter 4, Section 4.3.5: "Cannabis differs from alcohol; ... it seems not to increase risk-taking behavior. This may explain why it appears to play a smaller role than alcohol in road traffic accidents."]

  • krymsun krymsun Posts:

    Studies have shown marijuana users are Safer Drivers than either drunk drivers, or sober ones. One study, entitled "Medical Marijuana Laws, Traffic Fatalities, and Alcohol Consumption" conducted in November 2011 provides evidence that marijuana is a safer substitute for alcohol when it comes to health and also makes for safer drivers. Top Ten Reasons Marijuana Users Are Safe Drivers When you combine all of the main results of these two decades worth of scientific research studies, the following 10 reasons marijuana drivers are safer than drunk drivers comes out like this: 1. Drivers who had been using marijuana were found to drive slower, according to a 1983 study done by U.S. National Highway Transportation Safety Administration (NHTSA). This was seen as a factor in their favor, since drivers who drank alcohol usually drove faster and that is part of the reason they had accidents. 2. Marijuana users were able to drive straight and not have any trouble staying in their own lanes when driving on the highway, according to a NHTSA done in 1993 in the Netherlands. The study determined also that the use of marijuana had very little effect on the person’s overall driving ability. 3. Drivers who had smoked marijuana were shown to be less likely to try to pass other cars and to drive at a consistent speed, according to a University of Adelaide study done in Australia. The study showed no danger unless the drivers had also been drinking alcohol. 4. Drivers high on marijuana were also shown to be less likely to drive in a reckless fashion, according to a study done in 2000 in the UK by the UK Transport Research Lab. The study was done using drivers on driving simulators over a period of a month and was actually undertaken to show that pot was a cause for impairment, but instead it showed the opposite and confirmed that these drivers were actually much safer than some of the other drivers on the road. 5. States that allow the legal use of marijuana for medical reasons are noticing less traffic fatalities; for instance, in Colorado and Montana there has been a nine percent drop in traffic fatalities and a five percent drop in beer sales. The conclusion was that using marijuana actually has helped save lives. Medical marijuana is allowed in 16 states in the U.S. 6. Low doses of marijuana in a person’s system was found by tests in Canada in 2002 to have little effect on a person’s ability to drive a car, and that these drivers were in much fewer car crashes than alcohol drinkers. 7. Most marijuana smokers have fewer crashes because they don’t even drive in the first place and just stay home thus concluded more than one of these tests on pot smoking and driving. 8. Marijuana smokers are thought to be more sober drivers. Traffic information from 13 states where medical marijuana is legal showed that these drivers were actually safer and more careful than many other drivers on the road. These studies were confirmed by the University of Colorado and the Montana State University when they compared a relationship between legal marijuana use and deaths in traffic accidents in those states. The studies done by a group called the Truth About Cars showed that traffic deaths fell nine percent in states with legal use of medical marijuana. 9. Multiple studies showed that marijuana smokers were less likely to be risk takers than those that use alcohol. The studies showed that the marijuana calmed them down and made them actually pay more attention to their abilities. All of these tests and research studies showed that while some people think that marijuana is a major cause of traffic problems, in reality it may make the users even safer when they get behind the wheel. 10. Marijuana smoking drivers were shown to drive at prescribed following distances, which made them less likely to cause or have crashes. .. stick *that* in your pipe, and smoke it!

  • krymsun krymsun Posts:

    Is Driving High on Marijuana Safer Than Driving Drunk? [ or driving sober?!! ] For decades, marijuana advocates have argued that pot has a significantly different effect on driving ability than alcohol. But if you take the word of one auto insurance company, stoned is actually the safest way to drive. is making that case based on years’ worth of scientific studies, including some from the US National Highway Transportation Safety Administration that found motorists under the influence of marijuana tended to drive slower and have accident responsibility rates lower than those of drug-free drivers.

  • krymsun krymsun Posts:

    Is Driving High on Marijuana Safer Than Driving Drunk? [ or driving sober?!! ] For decades, marijuana advocates have argued that pot has a significantly different effect on driving ability than alcohol. But if you take the word of one auto insurance company, stoned is actually the safest way to drive. is making that case based on years’ worth of scientific studies, including some from the US National Highway Transportation Safety Administration that found motorists under the influence of marijuana tended to drive slower and have accident responsibility rates lower than those of drug-free drivers.

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