Court rules, Illegal marijuana grow of any size only a misdemeanor in Michigan.
Past defendants may have grounds to fight their prior convictions.
Since the act’s passage in 2018, the outdated 1978 law has led to the charging and conviction of over 3,500 individuals, as per analysis shared by Michigan Supreme Court spokesperson John Nevin with MLive. A total of 1,072 people have been convicted under this law.
Those defendants may have grounds to fight their prior convictions.
Attorney Michael Komorn of the Komorn law firm specializes in cannabis defense and currently has several clients charged under felony marijuana possession laws.
In light of the Court of Appeals ruling, he plans to file motions requesting those charges be reduced to misdemeanors. Komorn said most prosecutors and police have already placed a low priority on marijuana enforcement, except for “certain pockets” of the state. “They’ll raid like the old days, come in with guns and masks and go through that whole process,” he said, “but their dilemma is, how do we charge somebody.
What, do you get charged with a misdemeanor? “I have a number of cases where they’ve seized property and not charged anybody. And you can only reap the benefits of forfeiture if you get a felony conviction.”
KOMORN LAW Michigan’s Top Cannabis Legal Defense
If you are facing any charges related to marijuana. Call us only if you want to fight them…that’s what we do
TIP: We get calls all the time with people who regret hiring a lawyer to represent them for cannabis related charges that didn’t know squat about the laws. One shouldn’t have to tell them about the law before they convince you to plea. Hire right the first time because you may not get a second chance to fix it! Ask the attorney questions.
The appellate court reviewed a case that arose from an August 2020 raid in Tuscola County. This raid was conducted by the state police-led Thumb Narcotics Unit, which operates across Huron, Tuscola, Sanilac, and Lapeer counties.
Tuscola County prosecutors have charged Kejbou with two crimes related to the 1978 drug law. This law stipulates that individuals found in possession of less than 20 marijuana plants may face a maximum sentence of four years in prison, while those possessing over 200 plants could face up to 15 years of imprisonment.
Based on the aforementioned felony charges, the Tuscola County Prosecutor’s Office further filed charges against Kejbou for the offense of possession of a firearm in connection with the commission of a felony.
Violations for exceeding allowed amounts range from civil infractions to misdemeanors.
As the act states,“subject to imprisonment unless the violation was habitual, willful, and for a commercial purpose or the violation involved violence,”
The panel determined that felony punishments were not applicable.
Officially, cannabis still remains federally prohibited under the Controlled Substances Act as a Schedule I substance. This classification is reserved for substances that are considered to lack any currently accepted medical use and have a high potential for abuse.
However, the U.S. Department of Health and Human Services recommended in August that cannabis be moved from Schedule I to Schedule III.
It’s an election year open the panderverse portal.
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When it rains down in legal problems it’s probably going to pour. So you better have an umbrella fund off to the side somewhere safe…hidden…out of reach…stashed.
If you don’t have the funds, you won’t get good representation…and then you’re easy prey for the prosecutors and law enforcement.
As the marijuana industry continues to grow and evolve in Michigan, it’s crucial for marijuana cultivators to understand the importance of having legal defense funds readily available.
Despite the legalization of marijuana in the state, there are still potential legal challenges and risks that growers may face.
Having legal funds at the ready applies to everyone from
state licensed entities
caregivers and patients
recreational growers and consumers
hemp cultivators.
Understanding the legal landscape for marijuana cultivation in Michigan
An overview of marijuana laws in Michigan
In recent years, Michigan has seen significant changes in its marijuana laws. In 2008, the state passed the Michigan Medical Marihuana Act, which allowed the use of medical marijuana for qualifying patients. Then, in 2018, Michigan voters approved the Michigan Regulation and Taxation of Marihuana Act, which legalized the recreational use of marijuana for adults.
Under these laws, individuals aged 21 and older can possess and cultivate marijuana in certain quantities. However, it’s important to understand the specific regulations and limitations that apply.
Recent developments and changes in marijuana legislation
The legislative landscape surrounding marijuana cultivation in Michigan is constantly evolving. It’s crucial for cultivators to stay informed about any new developments or changes in the law.
For example, in 2020, the Michigan Marijuana Regulatory Agency (MRA) issued emergency rules that introduced licensing requirements for commercial marijuana establishments, including cultivation facilities. These rules outline specific procedures and standards that growers must adhere to.
By keeping up with the latest legislation and regulations, marijuana cultivators can ensure they are operating within the bounds of the law and avoid potential legal complications.
Potential legal challenges faced by marijuana growers in Michigan
State and federal conflicts in marijuana regulations
One of the major challenges faced by marijuana growers in Michigan is the conflict between state and federal regulations. While marijuana cultivation may be legal under state law, it remains illegal at the federal level.
This discrepancy creates uncertainty and can expose growers to potential legal risks. Federal law enforcement agencies, such as the Drug Enforcement Administration (DEA), can still enforce federal marijuana laws, although they typically focus on larger operations and violations that involve other criminal activities.
Nevertheless, it’s important for marijuana cultivators to understand the potential consequences and navigate this legal gray area cautiously.
Risks associated with non-compliance in cultivation practices
Even within the framework of state laws, there are numerous regulations and requirements that marijuana cultivators must adhere to. Failure to comply with these rules can result in legal consequences, including fines, license revocation, and even criminal charges.
Common compliance issues include exceeding plant limits, improper labeling, inadequate security measures, and failure to follow proper cultivation and testing procedures. It’s crucial for cultivators to stay informed and ensure they are operating in accordance with all applicable laws and regulations.
The Importance of having legal defense funds for marijuana cultivators
The financial burden of legal defense in marijuana cultivation cases
Legal challenges can be financially draining, and marijuana cultivators are no exception. Defending oneself in a legal case can involve expensive legal fees, court costs, and potential fines or penalties. These financial burdens can quickly accumulate and become overwhelming.
Having legal defense funds set aside can help alleviate the strain and ensure that cultivators can afford proper legal representation when needed. It’s a proactive measure that cultivators should consider to protect themselves from unexpected legal challenges.
The benefits of proactive legal preparation
In the ever-changing world of marijuana legislation, being prepared is key. By setting aside legal defense funds, cultivators can take a proactive approach to potential legal challenges. This preparation allows cultivators to act swiftly when needed, securing legal representation and taking necessary steps to protect their interests.
Having legal defense funds in place also provides peace of mind. It allows cultivators to focus on their operations without constantly worrying about potential legal troubles, knowing they have the resources to defend themselves if the need arises.
Navigating the complexities of marijuana laws in Michigan
Understanding licensing and permitting requirements
Obtaining the necessary licenses and permits is crucial for marijuana cultivators in Michigan. The state has established a comprehensive licensing system to regulate commercial marijuana operations.
Understanding the specific requirements, application processes, and deadlines associated with licenses is essential. It’s advisable to seek legal counsel to ensure compliance with all licensing and permitting obligations.
Comprehending zoning restrictions and land use regulations
Zoning restrictions and land use regulations add another layer of complexity to marijuana cultivation in Michigan. Local municipalities have the authority to regulate the location and operation of marijuana establishments within their jurisdictions.
Cultivators must familiarize themselves with the zoning laws in their area and ensure their operations comply with the specified land use regulations. Failure to do so can result in costly legal disputes or even forced closure of the cultivation facility.
By staying informed and working within the boundaries of zoning and land use regulations, cultivators can avoid unnecessary legal complications and focus on their business objectives.
Securing legal representation: the role of a defense attorney in marijuana cultivation cases
When it comes to growing legal marijuana in Michigan, having a reliable and experienced defense attorney like Komorn Law by your side is crucial. While the state allows for the cultivation of recreational and medical marijuana, there may still be legal challenges that require professional legal assistance.
Qualifications and expertise to look for in a defense attorney
Finding the right defense attorney is essential to protect your rights and navigate the complexities of marijuana cultivation cases. Look for attorneys who specialize in cannabis law and have experience dealing with similar cases. They should have a deep understanding of the ever-changing marijuana regulations in Michigan and be familiar with the specific nuances of the industry.
The importance of attorney-client privilege and confidentiality
When discussing legal matters, confidentiality is key. Attorney-client privilege ensures that any information shared between you and your defense attorney remains confidential. This protection is crucial for open and honest communication, allowing you to provide your attorney with all relevant details without fear of it being used against you.
Costs and considerations of legal defense for marijuana growers in Michigan
While nobody likes to think about legal trouble, it’s essential to consider the potential costs associated with legal defense in the marijuana industry.
Evaluating the potential costs of legal defense
Legal defense can be expensive, and the cost will vary depending on the complexity of your case.
Factors such as the nature of the charges, the amount of evidence involved, and the length of the legal process can all impact the overall cost.
It’s wise to consult with prospective defense attorneys to get an estimate of the potential costs involved in your specific situation.
Factors to consider when budgeting for legal representation
When budgeting for legal representation, it’s crucial to assess your financial situation realistically. Consider factors such as attorney fees, court expenses, and any additional costs that may arise during the legal process. It’s wise to set aside a substantial amount or create a legal defense fund to ensure you have the necessary resources when they are needed most.
These funds should be stashed away somewhere to avoid being “confiscated” by law enforcement.
Preemptive measures: building a legal defense fund for marijuana cultivation
Being proactive and planning ahead can save you from unnecessary stress and financial strain in the event of legal disputes related to marijuana cultivation.
Strategies for setting aside funds for legal defense
One effective strategy is to establish a dedicated legal defense fund specifically for covering potential legal expenses. This fund should be separate from your regular business finances and set aside on a regular basis. By consistently contributing to this fund, you can accumulate the necessary resources over time, providing you with a safety net if legal issues arise.
Developing a comprehensive legal defense plan
Having a well-thought-out legal defense plan is essential. This includes not only financial preparations but also understanding the legal framework and regulations surrounding marijuana cultivation in Michigan. Stay abreast of any changes in the law and consult with your defense attorney to ensure you are always prepared to defend your rights.
Anything you say will be used against you! Call our office before you say anything —>
1. Is it necessary to have legal defense money if marijuana cultivation is legal in Michigan?
While marijuana cultivation may be legal in Michigan, there are still potential legal challenges and risks associated with the industry. Having legal defense funds readily available is crucial to navigate these complexities and protect your interests in case of any legal disputes or challenges that may arise.
2. How much should I budget for legal defense funds?
The amount to budget for legal defense funds may vary depending on various factors, such as the size of your operation, the level of risk involved, and the specific legal services you may require. It is recommended to consult with a legal professional to assess your unique situation and determine an appropriate budget for your legal defense funds.
3. Can I rely solely on compliance to avoid legal issues?
While compliance with marijuana laws and regulations is crucial, it is not a foolproof guarantee against legal issues. Laws and regulations can change, and misunderstandings or disputes may arise. Having legal defense funds in place ensures you are prepared to navigate any unforeseen legal challenges that may arise, even if you are operating in full compliance.
4. What steps can I take to minimize legal risks as a marijuana grower in Michigan?
To minimize legal risks as a marijuana grower in Michigan, it is important to stay informed about the latest laws, licensing requirements, and zoning regulations. Maintaining meticulous records and documentation, implementing robust compliance practices, and seeking legal counsel when needed are all proactive measures that can help mitigate legal risks associated with operating in the marijuana industry.
If you or someone you know has been accused of a crime or DUI. Call Komorn Law and turn the odds in your favor. Call Now 248-357-2550
DISCLAIMER This website and/or post may contain re-posted content, opinions, comments, ads, third party posts, outdated information, posts from disgruntled persons, posts from those with agendas, private stuff, work related information, non work related information and general internet BS. Therefore…Before you believe anything on the internet regarding anything and everything – do your research on “Official Government and State Sites”, Call the Michigan State Police, Check the State Attorney General Website and Consult an Attorney – Use Your Brain. You’re on the internet.
Michigan marijuana sales reached a record-breaking high in December, according to state data. While medical cannabis purchases have gradually decreased, the adult-use market has more than compensated for the drop, with total sales reaching an impressive $221.7 million – a staggering $9 million more than the previous record set in September.
The Cannabis Regulatory Agency (CRA) reported that December saw $208,318,037 in recreational cannabis sales and $13,419,377 from medical marijuana purchases, as first reported by New Cannabis Ventures. This remarkable surge in sales is indicative of the growing popularity of marijuana in Michigan and the potential of the industry to become a major economic driver in the state. With the legalization of recreational marijuana, Michigan is now one of the largest markets in the United States, and the industry is expected to continue to grow in the coming years.
If you or someone you know has been accused of a crime, DUI or Drugged Driving. Call Komorn Law and turn your defense into an offense. Call Now 248-357-2550
DISCLAIMER This post may contain re-posted content, opinions, comments, ads, third party posts, outdated information, posts from disgruntled persons, posts from those with agendas, private stuff and general internet BS. Therefore…Before you believe anything on the internet regarding anything – do your research on “Official Government and State Sites”, Call the Michigan State Police, Check the State Attorney General Website and Consult an Attorney – Use Your Brain. You’re on the internet.
Our Machine-Learning algorithms scan the text for the most important phrases or passages. These highlights, alongside their respective section titles, are shown below.
Introduction
Saito et al. reported a validated gas chromatography-mass spectrometry (GC/MS) method with a LOQ of 0.4 ng THC/patch and found concentrations of 0.9 to 3.1 ng THC/patch in several 24-hour sweat patches from one cannabis user [20]. The expected disposition of THC in sweat from chronic cannabis users has not been reported.Go To Passage
Subjects And Study Design
Exact times of dosing were recorded, but target times each day were 0800, 1300 and 1730 h. After five consecutive dosing days, there was a 10-day washout period prior to the next dosing condition. Subjects had five dosing conditions involving placebo, low-dose liquid hemp oil (9 μg/g or a daily dose of 0.39 mg THC), low-dose hemp oil in capsules (92 μg/g or a daily dose of 0.47 mg THC), high-dose hemp oil (347 μg/g or a daily dose of 14.8 mg THC) and dronabinol (2.5 mg/capsule or a daily dose of 7.5 mg THC). Sweat patches were stored at −20°C until THC analysis.Go To Passage
Gc/Ms Analysis
Percent recovery from patches was 44-46%, LOQ was 0.4 ng THC/patch and coefficients of variation were < 10%. All weekly patches were tested. Some daily patches were not tested if no THC was found in the corresponding weekly patch.Go To Passage
Results
During this washout phase, the first weekly sweat patch from two of seven subjects had THC above the assay LOQ. One weekly patch contained 0.93 ng THC/patch, with none of the seven daily sweat patches worn this week positive for THC. The other weekly sweat patch contained 0.82 ng THC/patch, with only the first daily patch positive for THC at 0.44 ng of THC/patch.Go To Passage
Discussion
The manufacturer recommends that the patches be worn for one week. In the present study, sweat patches worn by daily cannabis users the first week of monitored abstinence had THC concentrations averaging 3.85 ng/patch. There are no other published studies reporting sweat patch THC concentrations after cessation of use for comparison.Go To Passage
Conclusions
Results of our clinical study indicate that daily cannabis users will excrete THC into sweat in concentrations above the SAMHSA cutoff of 1 ng/patch. During abstinence, negative patches are expected after one week, but some may have a longer washout period of four weeks or more. The sensitivity of sweat patches to detect new drug use following cannabis smoking is not known and requires an independent controlled smoked cannabis administration study.
Marilyn A. Huestis1,* , Karl B. Scheidweiler1, Takeshi Saito1,2, Neil Fortner3, Tsadik Abraham1, Richard A. Gustafson4, and Michael L. Smith5 1 Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA 2 Tokai University School of Medicine, Kanagawa, Japan 3 ChoicePoint, Inc., Alpharetta, GA 4 Lieutenant Commander, U S Navy, Navy Drug Screening Laboratory, Jacksonville, FL USA 5 Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, Rockville, MD, USA
DISCLAIMER This post may contain re-posted content, opinions, comments, ads, third party posts, outdated information, posts from disgruntled persons, posts from those with agendas and general internet BS. Therefore…Before you believe anything on the internet regarding anything – do your research on Official Government and State Sites, Call the Michigan State Police, Check the State Attorney General Website and Consult an Attorney – Use Your Brain.
This Study was released in 2010 but has very good information.
Abstract
The prevalence of both alcohol and cannabis use and the high morbidity associated with motor vehicle crashes has lead to a plethora of research on the link between the two. Drunk drivers are involved in 25% of motor vehicle fatalities, and many accidents involve drivers who test positive for cannabis. Cannabis and alcohol acutely impair several driving-related skills in a dose-related fashion, but the effects of cannabis vary more between individuals than they do with alcohol because of tolerance, differences in smoking technique, and different absorptions of Δ9-tetrahydrocannabinol (THC), the active ingredient in marijuana. Detrimental effects of cannabis use vary in a dose-related fashion, and are more pronounced with highly automatic driving functions than with more complex tasks that require conscious control, whereas with alcohol produces an opposite pattern of impairment. Because of both this and an increased awareness that they are impaired, marijuana smokers tend to compensate effectively while driving by utilizing a variety of behavioral strategies. Combining marijuana with alcohol eliminates the ability to use such strategies effectively, however, and results in impairment even at doses which would be insignificant were they of either drug alone. Epidemiological studies have been inconclusive regarding whether cannabis use causes an increased risk of accidents; in contrast, unanimity exists that alcohol use increases crash risk. Furthermore, the risk from driving under the influence of both alcohol and cannabis is greater than the risk of driving under the influence of either alone. Future research should focus on resolving contradictions posed by previous studies, and patients who smoke cannabis should be counseled to wait several hours before driving, and avoid combining the two drugs.
1. Introduction
Accidents are the fifth leading cause of death in the US; nearly half are motor vehicle accidents, which according to the Fatality Analysis Reporting System (FARS) killed 38,588 people in 2006 alone.1 Motor vehicle accidents are the nation’s leading cause of death in those under 30.2 The contribution of drugs of abuse to this accident rate has attracted increasing attention in recent years because of the dramatic increase in drug use. In 2002, the National Survey on Drug Use and Health (NSDUH) estimated that 22 million Americans—9.4% of the population—have a substance use or dependence problem. As marijuana is the most commonly used drug of abuse, having been tried by 40% of the population,3 and is also smoked most commonly in the age group that also has the most road traffic accidents, the contribution of marijuana smoking to road traffic accidents is of great concern to both governments and clinicians responsible for counseling patients with substance abuse problems. Moreover, given the paucity of data supporting marijuana’s acute toxicity, the most serious possible consequence of acute cannabis use is a road traffic accident from driving while intoxicated.4 The very high cost of crashes, both human and financial, underlines the importance of understanding the extent to which marijuana use contributes to such accidents. The purpose of this paper is to review the scientific evidence on the effects on driving while intoxicated with marijuana and contrast this with the effects of alcohol intoxication.
Looking for a frontline attorney that will fight in the trenchbeside you against the “justice” system ? Attorney Michael Komorn – provides aggressive DUI, drugged driving and criminal defense. Call The Office 248-357-2550 or visit KomornLaw.com
2. Epidemiology of marijuana smoking and road traffic accidents
The rising prevalence of cannabis use, its increased availability and potency,5 lower prices, widespread social tolerance, and earlier age of onset of use have combined to increase the number of users and hence the number of people subject to cannabis use disorders.6 Peak initiation is at age 18, and ten years later, 8% of users are marijuana-dependent.7 Most cannabis use is intermittent and time-limited, however; users generally stop in their mid-to-late 20s, and only a small minority continue in daily use over a period of years.8
Young people also account for a disproportionate number of road traffic accidents. According to the National Center for Statistics and Analysis, the fatality rate for teenagers is four times that of drivers age 25 to 69, and drivers under age 25 account for a quarter of all traffic fatalities.9 Risk factors for having a fatal traffic accident include being a young man, having psychological characteristics such as thrill-seeking and overconfidence, driving at excessive speed, driving late at night, failing to wear a seatbelt, and lacking familiarity with the vehicle.10 The risk factors for adolescent marijuana use are somewhat overlapping—delinquency (vandalism, shoplifting, joyriding etc.), poor school performance, and substance use by self and peers.11
The National Highway Transportation Safety Administration (NHTSA) reported that in 25% of all motor vehicle crash fatalities, the driver had a blood alcohol concentration (BAC) of 0.01 g/dL (one eighth the legal limit) or greater, and in 21-year-old drivers, that figure rose to 39%.12 Drivers with a previous DWI (“Driving While Impaired”) conviction were responsible for 7.2% of all crashes involving alcohol.
In comparison, the percentage of road traffic accidents in which one driver tested positive for marijuana ranges from 6% to 32%.13, 14 In one study, 9.7% of cannabis smokers reported having driven under the influence in the previous year; those who did drove while intoxicated an average of 8.1 times during the year.15 Among those who seek treatment for cannabis problems, more than 50% report having driven while “stoned” at least once in the previous year.16, 17
3. Studies relevant to marijuana and smoking
Three types of studies are generally performed to help assess the risk that smoking marijuana may increase the probability of having a fatal traffic accident. The first are cognitive studies that measure the effects of smoking marijuana on cognitive processes that are considered to be integral to safe driving. The second are experimental studies on the collision risk of people under the influence of marijuana. The third are descriptive and analytic epidemiological studies on the relationship between cannabis use and accidents, usually performed through drug testing of injured drivers.
3.1 Cognitive studies
Attentiveness, vigilance, perception of time and speed, and use of acquired knowledge are all affected by marijuana;18–21 in fact, a meta-analysis of 60 studies concluded that marijuana causes impairment in every performance area that can reasonably be connected with safe driving of a vehicle, such as tracking, motor coordination, visual functions, and particularly complex tasks that require divided attention,22 although studies on marijuana’s effects on reaction time have been contradictory.23 Similar conclusions have been reached by other reviewers.2 Worse still, marijuana and alcohol, when used together, have additive or even multiplicative effects on impairment.24 Consequently, on the basis of cognitive studies, it seems reasonable to propose that smoking marijuana may increase the risk of having a fatal traffic accident.
Alcohol at 0.75 g/kg (slightly less than four standard drinks) causes high levels of impairment in psychomotor performance and medium-to-high levels of impairment in such tasks as critical flicker fusion and short-term memory.25 Alcohol impairs pursuit tracking, divided attention, signal detection, hazard perception,26–28 reaction time, attention, concentration, and hand-eye coordination.29, 30
Alcohol also reduces the perceived negative consequences of risk-taking,31 which can increase willingness to take risks after drinking,32 the amount of risk-taking behavior while driving, even at low alcohol doses,33 and the incidence of road traffic accidents while driving drunk.34, 35 However, there is considerable variability in the effects that alcohol can have on people—the same dose may have different effects not only on different individuals, but also in the same individual on different occasions, because of other factors such as gender, body mass index, age, drinking habits, time of day, stomach contents, genetics, stage of the menstrual cycle, and environmental factors.36
3.2 Experimental research (driving and simulator studies)
Experimental research measures the potential risk of an accident using a driving simulator or driving course.
3.2.1 Studies that do not show impairment
Surprisingly, given the alarming results of cognitive studies, most marijuana-intoxicated drivers show only modest impairments on actual road tests.37, 38 Experienced smokers who drive on a set course show almost no functional impairment under the influence of marijuana, except when it is combined with alcohol.39
Many investigators have suggested that the reason why marijuana does not result in an increased crash rate in laboratory tests despite demonstrable neurophysiologic impairments is that, unlike drivers under the influence of alcohol, who tend to underestimate their degree of impairment, marijuana users tend to overestimate their impairment, and consequently employ compensatory strategies. Cannabis users perceive their driving under the influence as impaired and more cautious,40 and given a dose of 7 mg THC (about a third of a joint), drivers rated themselves as impaired even though their driving performance was not; in contrast, at a BAC 0.04% (slightly less than two “standard drinks” of a can of beer or small 5 oz. glass of wine; half the legal limit in most US states), driving performance was impaired even though drivers rated themselves as unimpaired.41 Binge drinkers are particularly likely to rate themselves as unimpaired, possibly because they tend to become less sedated by high doses of alcohol.42
This awareness of impairment has behavioral consequences. Several reviews of driving and simulator studies have concluded that marijuana use by drivers is likely to result in decreased speed and fewer attempts to overtake, as well as increased “following distance”. The opposite is true of alcohol.43 One review of eight driving simulator studies and seven on-road studies44 found that cannabis use was associated with either poor lane control41, 45–48 or slower driving that successfully maintained lane control.49–51 In seven of ten studies cited, cannabis use was associated with a decrease in driving speed despite explicit instructions to maintain a particular speed, whereas under the influence of alcohol, subjects consistently drove faster. Two simulator studies showed that the tendency to overtake was decreased with cannabis use but increased with alcohol.52, 53 One simulator study and two on-road studies examining car-following behavior concluded that cannabis smokers tend to increase the distance between themselves and the car in front of them.41, 45 Other studies have found no adverse effects of marijuana use on sign detection,49 a sudden lane-changing task,43 or the detection of and response to hazardous events.48
3.2.2 Studies that show impairment
Not all deficits can be compensated for through the use of behavioral strategies, however. Both alcohol and marijuana use increase reaction time and the number of incorrect responses to emergencies.43 Drivers under the influence of marijuana were not able to compensate for standard deviation of lateral position (SDLP, a measure of staying within lane), which increased with increasing doses of THC. This is a measure that is not subject to conscious compensatory mechanisms in the way that other aspects of driving are. Other studies have found poorer monitoring of the speedometer under the influence of marijuana,54 increased decision time when passing,52 increased time needed to brake when a light suddenly changes,55 and increased time to respond to a changing light45, 56 or sudden sound.57 Drivers also crashed more frequently into a sudden obstacle on a high dose of marijuana, although this did not happen at a low dose.45
Meta-analyses of over 120 studies have found that in general, the higher the estimated concentration of THC in blood, the greater the driving impairment, but that more frequent users of marijuana show less impairment than infrequent users at the same dose, either because of physiological tolerance or learned compensatory behavior. Maximal impairment is found 20 to 40 minutes after smoking, but the impairment has vanished 2.5 hours later, at least in those who smoke 18 mg THC or less (the dose often used experimentally to duplicate a single joint).58, 59
With increasing doses of alcohol, however, there is general dose-dependent lowering of both sustained attention and overall attentional capacity, with consequently more concentration paid to the main component of a complex skill (steering, for example), and less and less attention paid to secondary tasks (such as speed or driving skill). Functional imaging on the effects of increasing doses of alcohol up to a BAC of 0.08% in simulated driving has demonstrated that orbitofrontal areas (subsuming judgment) and motor areas are affected first, then cerebellar areas controlling coordination show functional deterioration, and finally, at high doses, global cognitive networks and simulated driving performance are impaired.60
Interestingly, three reports indicate that chronic marijuana smokers are less susceptible to impairment from alcohol on some measures compared with nonsmokers or infrequent smokers. As far back as 1970, Reese Jones noticed that alcohol’s effects were diminished in heavy cannabis smokers.61 A subsequent study showed that regular cannabis smokers demonstrate less of a decrement in peripheral signal detection under the influence of alcohol than do infrequent users,62 and a later study still found that regular cannabis users given alcohol alone showed less of a decrement in tracking accuracy and dizziness ratings than infrequent users given the same alcohol dose.63 The reason for this is unclear, but is hypothesized to result from either pharmacological or behavioral cross-tolerance between marijuana and alcohol.
3.2.3 Summary of experimental studies
It appears that cannabis use may impair some driving skills (automatic functions such as tracking) at smoked doses as low as 6.25 mg (a third of a joint), but different skills (complex functions that require conscious control) are not impaired until higher doses, and cannabis users tend to compensate effectively for their deficits by driving more carefully. Unexpected events are still difficult to handle under the influence of marijuana, however, and the combination of low-dose alcohol and low-dose cannabis causes much more impairment than either drug used alone.48, 64, 65 Alcohol appears to impair tasks requiring cognitive control more than it does automatic functions, whereas marijuana at a comparable dose impairs automatic functions more than those requiring cognitive control. Together, the effects on impairment are additive and may even be synergistic. Chronic marijuana smokers are less impaired by both alcohol and marijuana than would be expected, however.
3.3 Epidemiologicalstudies
One weakness of driving studies is that subjects are aware of being observed and assessed, so such studies are generally a better measure of what drivers are capable of doing rather than what they actually do. Epidemiological studies attempt to assess the actual risk that a driver may cause an accident under the influence of a drug, relative to that of a sober person driving under similar conditions. The relative risk is expressed in the form of an “odds ratio” (OR), which is the multiplier for the increased accident risk from driving under the influence of marijuana. Two approaches are taken. The first is culpability studies, which classify drivers who have crashed according to their degree of responsibility for the crash, then compare drug use in each category. If there is greater use of the drug in those culpable for crashes, then the drug is judged to be responsible for a greater crash risk. The second is case control studies. We will discuss both in turn.
3.3.1 Culpability studies
3.3.1.1 Studies that do not show culpability
Some reviewers have concluded that there is no evidence that cannabis alone increases the risk of culpability for crashes, and may actually reduce risk.66 Drummer’s review of blood samples of traffic fatalities in Australia found that drivers testing positive for marijuana were actually less likely to have been judged responsible for the accident.67 Several other studies have found no increase in crash risk with cannabis.68–70 Williams’ California study of 440 male traffic accident deaths found that while alcohol use was related to crash culpability, cannabis use was not.71 Terhune’s study of 1882 motor vehicle deaths calculated an OR of 0.7 for cannabis use, 7.4 for alcohol use, and 8.4 for cannabis and alcohol use combined.68 Lowenstein and Koziol-McLain’s study of 414 injured drivers admitted to a Colorado E/R found an OR of 1.1, indicating that marijuana use was not associated with increased crash responsibility.72 Drummer’s later and more extensive ten-year study of 3400 traffic fatalities in three Australian states found that drivers with blood THC levels less than 5 ng/mL, and those with only carboxy-THC present (THC-COOH, a metabolite that is excreted in the urine for weeks and is thus more likely to indicate past use than current use), had an OR of 1.0, but those with serum levels greater than 5 ng/mL had an OR of 6.6, the same as that for a BAC of 0.15%. In all 30 cases in this study in which one driver had a serum level of THC greater than 10 ng/mL, that driver was judged to have been responsible for the accident. When marijuana was combined with alcohol, the risk was higher still.73 A later reanalysis of the same data that adjusted for the age and sex of the fatalities found that OR of crashing for cannabis use alone dropped to 0.6 (not significantly different from 1.0), versus 7.6 for alcohol.66 Laumon’s study of 10,748 French motor vehicle fatalities found that although rates of alcohol and cannabis intoxication were similar (nearly 3%), ten times as many crashes were associated with alcohol as with cannabis; however, investigators noted a dose-dependent effect on OR with increasing THC serum levels, confirming Drummer’s observation by calculating an OR of 4.72 for THC levels greater than 5 ng/mL.74 Longo’s large, well-known study of hospitalized injured drivers in South Australia showed few adverse effects of cannabis on crash risk, although there was a slightly increased risk of crashing with higher THC concentrations and a slightly lower risk with lower concentrations.75
What 5 ng/mL means in terms of actual impairment is hard to calculate, as THC levels in the blood peak quickly following inhalation then decrease rapidly according to complex pharmacokinetics, making it almost impossible to extrapolate backwards from the concentration of THC at the time of the blood test to the concentration at the time of the traffic accident. Some insight can be gained from Jones’ study of 1276 Swedish motorists arrested for DUI with blood tests positive for THC alone, which revealed an average THC blood level of 3.6 ng/mL at the time of testing.76 A similar Swiss study of 440 DUI suspects who also were positive for only THC found average blood concentrations of 5.0 ng/mL at the time of testing, indicating that a residual level of 5 ng/mL does appear to correlate with observable driving impairment earlier.77 The Swedish study also found that, of the 291 DUI arrestees who were positive for both THC and alcohol, the average THC blood level was only 2.3 ng/mL, again suggesting that lower levels of THC, when combined with alcohol, are sufficient to cause obvious impairment.76
Methodological problems often can make culpability studies hard to interpret, however. Since no study has ever shown an increased risk of road accidents among frequent marijuana smokers who are not intoxicated at the time that they drive, a positive urine test that measures levels of the long-lasting metabolite carboxy-THC but not the active ingredient THC is insufficient to classify a driver as intoxicated, as such a measure will include in the marijuana group unimpaired people who have smoked only in the past and thus artificially depress the OR.78 The Colorado study that found that marijuana use was not associated with increased crash responsibility used urine toxicology to assess drug use, so likely suffered from this limitation.72 Sampling delays in excess of an hour can cause an underestimation of THC concentration in the blood of injured drivers who test positive for marijuana, possibly explaining Longo and others’ failure to find adverse effects.
Alcohol levels, which have linear pharmacokinetics, are easier to back-calculate to the time of the accident, and are consistently linked with increased culpability in crashes.71, 75 Moreover, whereas CNS levels of alcohol, which moves easily throughout the body with little difference in concentration between compartments, can be approximated with a good degree of accuracy through measuring blood or breath levels, the same is not true of THC, which is highly lipophilic and concentrates preferentially in adipose tissue. Consequently, experimental studies have shown that functional impairment (which reaches a maximum an hour after smoking) lags behind THC blood level (which peaks within minutes and decreases rapidly thereafter).79 (Figure 1) This makes it much harder to generate blood level versus impairment curves for marijuana than it is for alcohol.
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