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Title PageEffects of Marijuana Legalization Policies on Fatal Car Accidents Throughout the Fifty StatesbyAlana Celine AlameidaBS in Nursing, University of Pittsburgh, 2017Submitted to the Graduate Faculty of theDepartment of EpidemiologyGraduate School of Public Health in partial fulfillment of the requirements for the degree ofMaster of Public HealthUniversity of Pittsburgh2020Committee PageUNIVERSITY OF PITTSBURGHGraduate School of Public HealthThis essay is submitted byAlana Celine AlameidaonAugust 14, 2020and approved byEssay Advisor: Anthony Fabio, PhD, Associate Professor, Department of Epidemiology, Graduate School of Public Health, University of PittsburghEssay Reader: Thomas J. Songer, PhD, Assistant Professor, Department of Epidemiology, Graduate School of Public Health, University of PittsburghEssay Reader: Ada Youk, PhD, Associate Professor, Department of Biostatistics, Graduate School of Public Health, University of PittsburghCopyright ? by Alana Celine Alameida2020AbstractAnthony Fabio, PhDEffects of Marijuana Legalization Policies on Fatal Car Accidents Throughout the Fifty StatesAlana Celine Alameida, MPHUniversity of Pittsburgh, 2020AbstractMarijuana use is rapidly becoming more prevalent and accepted throughout the United States with repercussions for the public health and medical systems. Though cannabinoids remain a schedule I drug at the federal level, an increasing amount of states are passing more permissive marijuana policies at the state level. Previous research on the effects of marijuana have focused on symptomatic consequences including driving impairment, capacity for addiction, and growing therapeutic use, but studies on the associations between degree of legalization and marijuana use have been historically inconclusive. An original injury epidemiology research report was conducted using the Fatality Analysis Reporting System (FARS) to investigate total fatalities from motor vehicle accidents (MVAs) and marijuana involvement in fatal MVAs by degree of legalization. The results indicate that the odds of positive marijuana test in fatal MVAs increased with decriminalization (OR 1.34, 95% CI 1.29-1.39), medical legalization (OR 1.61, 95% CI 1.58-1.65), and recreational legalization (OR 2.33, 95% CI 2.24-2.42) when compared to illegalization and after controlling for age, sex, race, alcohol use and time in months. A similar result was observed with increasing policy permissiveness being slightly associated with the number of individuals testing positive for marijuana at the medical (0.25 more persons each state per month per 1,000,000, p=0.0001) and recreational (0.44 more persons each state per month per 1,000,000, p<0.0001) legalization stages though decriminalization was not statistically significant (p=0.7703). Deaths from car crashes were also positively associated at the decriminalized (0.12 more persons each state per month per 1,000,000, p<0.0001), medical (0.67 more persons each state per month per 1,000,000, p<0.0001), and recreational (3.31 more persons each state per month per 1,000,000, p<0.0001) legalization stages after controlling for state and time. Though caution should be taken in interpreting results from a biased dataset, there is evidence to suggest that marijuana policy could influence traffic safety as states continue to pass more permissive legislation, requiring an appropriate public health response.Table of Contents TOC \o "3-4" \h \z \t "Heading 1,1,Heading 2,2,Heading,1,App Section,2,Appendix,1" 1.0 Introduction PAGEREF _Toc48249115 \h 11.1 Marijuana Epidemiology PAGEREF _Toc48249116 \h 11.2 Impact on Operating Vehicles PAGEREF _Toc48249117 \h 31.3 Marijuana Policies and Law PAGEREF _Toc48249118 \h 41.4 Legislation and Public Health Significance PAGEREF _Toc48249119 \h 72.0 Objectives PAGEREF _Toc48249120 \h 93.0 Methods PAGEREF _Toc48249121 \h 103.1 FARS Database PAGEREF _Toc48249122 \h 103.2 Other Sources PAGEREF _Toc48249123 \h 113.3 Statistical Analyses PAGEREF _Toc48249124 \h 124.0 Results PAGEREF _Toc48249125 \h 145.0 Discussion PAGEREF _Toc48249126 \h 18Appendix A Tables PAGEREF _Toc48249127 \h 22Appendix B Figures PAGEREF _Toc48249128 \h 35Bibliography PAGEREF _Toc48249129 \h 37List of Tables TOC \h \z \c "Table" Table 1. Odds Ratios of Crashes Involving Marijuana by Policy Level PAGEREF _Toc48078708 \h 15Table 2. Marijuana Involvement and Death by Policy Level Per State Per Month PAGEREF _Toc48078709 \h 16 TOC \h \z \c "Appendix Table" Appendix A Table 1. Marijuana Laws by State (August 2020) PAGEREF _Toc48154389 \h 22Appendix A Table 2. Demographics of Individuals Involved in Car Crashes28Appendix A Table 3. Significant Odds Ratios of Marijuana Involvement by State PAGEREF _Toc48154391 \h 30Appendix A Table 4. Deaths in Car Crashes per Month by State and Policy Level Adjusted per 1,000,000 PAGEREF _Toc48154391 \h 31Appendix A Table 5. Marijuana Involvement in Car Crashes per Month by State and Policy Level Adjusted per 1,000,000 PAGEREF _Toc48154391 \h 33List of Figures TOC \h \z \c "Appendix Figure" Appendix B Figure 1. Crash Deaths in California from 2004-2018 by Marijuana Policy PAGEREF _Toc48256073 \h 35Appendix B Figure 2. Crash Deaths in Massachusetts from 2004-2018 by Marijuana Policy PAGEREF _Toc48256074 \h 36IntroductionMarijuana EpidemiologyThe United Nations globally estimates that as of 2015, between 2.7-4.9% of the world’s population have tried marijuana at least once in a recent timeframe, or as many as ten times the amount of people that have tried other internationally regulated drugs such as opiates and cocaine. Prevalence of marijuana use is most often estimated as “consumption within twelve months”, though some studies use intervals as short as 30 days1. Marijuana is one of the most commonly used psychotropic substances in the nation, trailing behind alcohol and eclipsing tobacco in recent years2. The National Center for Drug Abuse Statistics (NCDAS) estimates that 55 million or 16.9% of American adults currently use marijuana, and 3,700 adolescents are exposed to the drug for the first time daily3. Marijuana is used more often by men than women and is most popular between the ages of 18-25. As of July, 2020, 11 states and the District of Columbia have fully legalized marijuana while 27 others have legalized it for medical use.Cannabis and marijuana are terms often used interchangeably but have crucial differences in the realms of policy and legality. Cannabis or cannabinoid products refer to all the derivatives of the Cannabis plant, of which there are three species: C. sativa, C. indica, and C. ruderalis, though some can be considered subtypes of others. Chemical substances produced by the plant are called cannabinoids, the primary psychoactive component of which is tetrahydrocannabinol (THC) which is a source of contention in medical marijuana policy and recreational marijuana policy (mMP and rMP) within the country.Marijuana is any cannabis product that contains a significant amount of THC and can be consumed in a variety of methods including as a food, extract, smoking, and vaping. Natural cannabis plants contain anywhere from 10-15% THC and the THC:CBD ratio varies significantly, though studies suggest a ratio of 1:1 has the greatest therapeutic potential for least risk4. Derivatives of cannabis that contain scant amounts of THC (<0.3%) are considered industrial hemp. Cannabinol, which is a cannabinoid, does not have psychoactive properties and can be extracted from marijuana or hemp5. It is used in several pharmaceutical drugs and under certain state laws CBD oil is classified differently to higher THC content products in their medical legalization status. There is no known lethal dose of THC in humans, as no human has been recorded dying from the substance alone. Doses of up to 9000mg/kg were non-lethal in dogs and monkeys, whereas death occurred in rats between THC concentrations of 225-3600mg/kg6.The U.S. Food and Drug Administration (FDA) has not approved the cannabis plant for medical use or the use of THC and CBD for dietary supplements. It has however approved specific pharmaceutical drugs that use synthetic THC substances like dronabinol (in Marinol and Syndros) and nabilone (in Cesamet). These drugs are indicated for treating nausea, emesis, and anorexia due to conditions like HIV/AIDS and cancer therapies7. Medical marijuana-inclusive drugs have also been used off-label for moderate benefit for other conditions including epilepsy, chronic pain, and headaches. As the purpose of this project is to investigate whether the psychoactive component of marijuana and its availability influences fatal car accidents, states with highly restrictive mMPs allowing only for products with THC content <0.5% will not be classified as having adequate mMPs in place.Marijuana is currently federally classified as a Schedule I drug with high risk for abuse alongside other substances such as diacetylmorphine (heroin), lysergic acid diethylamide (LSD) and 3,4-methylenedioxymethamphetamine (MDMA / ecstasy)8. This designation has sparked controversy among clinicians and scientists alike over the substance’s debated addictiveness and role as a ‘gateway drug’4. Schedule I drugs are considered to have no medical value, cannot be prescribed, and can only be distributed for federally approved research. Even in states with medical marijuana laws, healthcare providers and physicians cannot prescribe medical marijuana, only recommend its use. Patients that have a qualifying condition often need to acquire it through specific dispensaries or authorized entities that can manufacture and distribute the substance9.The effects of marijuana vary greatly by pharmacokinetics. Composition of tetrahydrocannabinol (THC) and cannabidiol (CBD), the route of administration (oral, smoking, vaporized, extract), and the dosing value all result in effects that can deviate based on the individual. Adverse events resulting from the drug are typically related to its THC component, with a total daily dose equivalent recommended not to exceed 30mg/day or in conjunction with CBD to “avoid psychoactive sequelae and development of tolerance”10. There is a growing body of evidence that supports the medical indication of marijuana in neurologic, psychiatric, and pain-related disorders11-12 as well as headache, migraine, and to assist in opioid detoxification13. In contrast, chronic marijuana use has also been associated with poorer educational outcomes, early school-leaving, addiction, depression, cognitive impairment, and cannabis-related car accidents14-15.Impact on Operating VehiclesFor drivers who are involved in motor vehicle accidents (MVAs) and / or are reported as drug-impaired, cannabinoids are the most common psychoactive substance discovered in the blood16 and are associated with an three to seven times increase in culpability than non-impaired drivers17-20. Current literature demonstrates a direct association between cannabis and impaired driving ability19,21-23. Some studies have affirmed that THC selectively impacts certain driving tasks worse than others, and that users tend to compensate by driving more slowly but control diminishes for more complex tasks23. Highly automated activities such as self-correcting road tracking were more affected than conscious control24. Combining alcohol and THC products has been shown to increase the odds of driver error additively rather than synergistically compared to their constituents alone22.Though a wealth of evidence supports the deterioration of driving ability with increasing cannabis consumption, preventing driving under the influence of cannabis (DUIC) proves a difficult task considering public perception. A majority of surveyed DUIC drivers believed cannabis provided minimal driving risk, that risks could be compensated by experience, and indicated that they were likely to reoffend for DUIC in the future19. However, epidemiological findings and their experimental counterparts have sometimes disagreed over the degree of cannabis effects on operating motor vehicles25. A large case-control study conducted by the National Highway Traffic Safety Administration found no significant increased crash risk attributable to cannabis after controlling for drivers’ age, gender, race, and presence of alcohol.26,20.Marijuana Policies and LawMarijuana legislation was first enacted in 1937 with the Marijuana Tax Act, with enormous variation in policy within the states and over the decades since. One of the most important consolidations of federal law concerning the substance was the Controlled Substance Act of 1970 as part of President Nixon’s “War on Drugs’ campaign. This classified marijuana as a schedule I drug with no redeemable medical benefit, and though the statute has been revised multiple times up until the year 2017 it has made it difficult to study the effects of marijuana use in the United States population in relation to its increasing consumption27, particularly for medical purposes.While public perception throughout the U.S. is shifting towards being receptive of legalization28, long-term consequences of marijuana consumption especially among chronic users is poorly understood and its risks potentially downplayed by advocates. ‘Home-grown’ marijuana that has become more prevalent with legalization laws poses perhaps the most significant risk, having higher THC concentrations that have been associated with increased psychoactive states such as paranoia, psychosis, and aggression, especially in individuals with pre-existing mental disorders29. Psychosis risks have been found to be greater in chronic users that begin in adolescence, but marijuana legalization has been more associated with adult use than adolescent use30. Research within the past two decades suggests that DUIC approximately doubles the risk of having a motor vehicle accident (MVA) and, in adolescents, doubles the risk of early drop-out from school as well as contributing to cognitive impairments and other illicit drug use into adulthood15. Legalization has also shown a decrease in perceived harmfulness and increase in marijuana use among teenagers31.Investigating the diverse sociocultural factors that precipitate marijuana use requires understanding the convoluted policies that define its use. Policies vary over time and between states, which rarely transition from an illegal state to recreational state but instead have overlapped laws with increasing degree of permissiveness throughout the years. Most current states that have legalized marijuana use had first decriminalized certain possession offenses, followed by allowing for medical marijuana exemptions, and then settling on legalization. As a result of this recent experimentation with legalization and the degrees of complexity surrounding decriminalization and patient medical access laws, both public perception and epidemiological research on widespread marijuana effects on society can be obfuscated. There is a dearth of literature on the effects of marijuana pre- and post-legalization, and existing literature with slow or inconclusive findings which can create the illusion of harmlessness for the drug. Previous evaluations of legislation on marijuana and its effects have been primarily based on prevalence rates27, which noticeably do not encompass the difference between casual and chronic users and do not contain information on route of administration and dosage of the drug.For the purposes of this report, marijuana policies are classified according to their four levels of legal definition. Prohibition outlaws the use of marijuana entirely, including actions such as possession, cultivation, sale, and distribution. Decriminalization is the reduction in penalties associated for cannabis offenses, typically civil instead of criminal penalties for smaller charges and was first championed by the Shaffer Commission in 1972. Currently, mMPs are state-based laws that increase access of cannabinoids for medical purposes only despite the federal government maintaining marijuana as a schedule I drug with no therapeutic value. In some cases, mMPs are seen as a veneer for legalization and rMPs, which is the final level of policy that removes criminal and monetary penalties and allows cannabis for recreational purposes32. The Insurance Institute for Highway Safety has created a table summarizing current marijuana laws by state as of August 202033, which can be viewed in Appendix A Table 1.Legislation and Public Health SignificanceThe heterogeneity of policies is a great concern for both practical and research implications28. The policies themselves, the population at the time which they address, the products they license, the state they are enacted in, the time period they are signed in comparison to when they take effect, and multiple other metrics can complicate outcomes and introduce lag effects that make establishing correlation and even causation difficult. Early studies on immediate effects of change in marijuana policy in the 1970s-1980s were inconsistent, especially in regard to decriminalization of marijuana. Consumption and prevalence patterns examined during this time period used crude measures which potentially contributed to the variance in methods and results34, especially when attempting to compare to other states which retained more severe penalties. Though decriminalization had not appeared to influence marijuana use rates, many states including California found significant cost savings in the criminal justice system as a result35. It is impossible to have a discourse on marijuana legalization, particularly early decriminalization policies, without the political factors of rising state budgetary costs, arrests, misdemeanor marijuana crimes and incarceration of nonviolent drug offenders36.Marijuana legalization is not only tied to the justice system but the sphere of public health. One of the more immediate impacts of cannabis use can be tied to traffic safety and emergency department visits. Between the years of 1973 and 1978 twelve states had decriminalized the possession of marijuana and during this time, metropolitan hospital emergency room data found a significant decrease in visits related to drug involvement of drugs other than marijuana, while episodes related to marijuana increased36.However, describing an association between marijuana legalization and marijuana outcomes through time is nuanced. Though Colorado voters approved recreational marijuana in November of 2012, retail sales did not begin until 2014. The delay in licensing manufacturers, creating dispensaries, and distributing marijuana to the public is difficult to quantify by state and by legislative act. As Colorado was also one of the first states to legalize recreational marijuana, marijuana tourism also became an acknowledged side effect of the process. A study of urban hospitals under the Colorado Hospital Association between the years of 2011 and 2014 found that in-state resident emergency department (ED) visits did not significantly change from 2011-2014, but out-of-state resident marijuana-related ED visits increased from 78 per 100,000 in 2011 to 163 per 100,000 visits in 2014, which marked the first year of retail sales38.Similarly, a study of a regional level-I trauma center found that approximately 60% of MVA admissions tested positive for alcohol or drugs in the blood, with more testing positive for drug use than alcohol34. Prior to its discontinuation, the Drug Abuse Warning Network (DAWN) estimated approximately 456,000 marijuana-related emergency department visits within the year 2011, an increase from previous years39. However, marijuana overdose itself was not necessary to be categorized as a marijuana-related visit. With even limited conclusive evidence of cannabis-related outcomes in the criminal justice, education and youth, medical, and public health fields, marijuana use and policy has become a key concern for both lawmakers and the public in recent years. As states continue to push towards legalization, the short and long-term effects of increasing marijuana use will become more prevalent and establishing a greater understanding of how it impacts the population is necessary to adequately prepare for the impending stressors it may place.ObjectivesThis essay examines as an independent variable four levels of marijuana policy (where marijuana is illegal, decriminalized only, medically legalized, and recreationally legalized) and what impact, if any, they have on the following three objectives including one sub-objective:Proportion of individuals involved in fatal crashes that tested positive for marijuana Proportion of drivers in fatal crashes that tested positive for marijuana by policy levelNumber of individuals involved in fatal crashes that tested positive for marijuanaNumber of deaths from fatal crashesMethodsFARS DatabaseData for this report was obtained from the National Highway Traffic Safety Administration’s (NHTSA) Fatality Analysis Reporting System (FARS) for the most recent fifteen years of complete data available (2004 to 2018). The final data consisted of N=1,280,256 total individuals involved in a car accident that lead to at least one fatality across the fifty states excluding the subgroup for the District of Columbia and U.S. territories such as the Virgin Islands and Puerto Rico. Total fatalities by crash ranged from 1 to 23 individuals, with 59.92% (n=767,087) of all involved individuals being drivers in-transport, 32.13% (n=411,332) being passengers in-transport, and the remaining 7.95% (n=101,837) of individuals being occupants of a vehicle not-in-transport, non-motorists such as pedestrians and cyclists, those in buildings, others, and unknowns. Numerous coding and referencing changes have been applied to the FARS database since its initiation in 1975. Some data sets were not available until a certain year onwards, some variables from previous datasets had been moved, renamed, or integrated into other variables as a result, and some attribute codes had been modified over time to increase clarity but for the most part were able to be retroactively applied to data from older years. There were a total of 44 variables used in the final data set which were compiled from four files per year (ACCIDENT and PERSON files which have been used since 1975, DRIMPAIR and NMIMPAIR which were in use from 2010 and onwards, and DRUGS, which moved some data from the PERSON file into a separate entity as of 2018). Information regarding these changes was obtained from the Fatality Analysis Reporting System (FARS) Analytical User’s Manual, 1975-2018.While police and state-level reporting and designations of drug use may vary, any individuals involved in a fatal car accident was considered to have been under the influence of marijuana if they were coded as testing positive for delta-9, hashish oil, hashish, marijuana, Marinol, or tetrahydrocannabinol (THC).Other SourcesThe degree of marijuana legalization among the fifty states was classified into three true or false variables: decriminalization, medical marijuana use permitted, and recreational legalization. This allows for easier coding of dummy variables in SAS as well as the ability to account for overlaps in degree of legalization, primarily with decriminalization being able to occur before and after medical marijuana legalization enactment. When combined they create one overall variable for legalization with the four stages as discussed in the introduction: illegal across the board, decriminalized only, medical legalization, and recreational legalization, with the latter categories overriding the earlier ones.As specific marijuana policies vary by state and within state by cities and municipalities, a state is only considered to fall under the four categories of legalization if they have the appropriate legislation passed at the state level. Additionally, a state is marked by the corresponding bill’s month of enactment instead of the date it was approved, as the delay between signing the legislation into law and when it becomes effective can span several months which can contribute to erroneous data. Legislation data was obtained from the National Conference of State Legislatures, Insurance Institute for Highway Safety and ballot research by state40,33. The smallest unit of time used in this report is months to preserve the most amount of data regarding the stage of legalization throughout the year within the states. However, census population estimates required for adjustment are only created annually and predicated on July 1st of every year. For this reason, all months within a year for each state will use the estimated population of that state for that year for all adjustment calculations. Population data was obtained from the United States Census Bureau’s 2000-2010 and 2010-19 Population Intercensal Estimates41.Statistical AnalysesThe statistical software used for analysis of this project was SAS. The FARS datasets provided by NHTSA were separated into files by year and as some files, codes, and variables changed throughout the data time span, modification was required to standardize the data if it had not already been processed retroactively. For the outcome variables, fatality counts remained consistent however the drug testing indicators and drug test results were moved into their own file in 2018, requiring additional processing to match the corresponding data of the previous fourteen years. The only files used for this analysis were those pertaining to the overall summary of accident data, the individual characteristics of those involved in the accidents, and any information regarding impairment and drug use. Three outcomes of interest were evaluated; the proportion of individuals involved in fatal crashes that test positive for marijuana (with the sub-category of the proportion of drivers in fatal crashes that test positive for marijuana), the number of individuals that test positive for marijuana use, and the number of deaths that occurred in the dataset. The number of deaths and number of individuals with a positive test were investigated first as a dichotomous variable and then as a frequency count which was further adjusted by population levels within the state during the year. The primary independent variable was level of legalization which contained four categories from most restrictive to least restrictive marijuana legislation: illegal, decriminalized only, medical legalization, and recreational legalization. States that had decriminalized marijuana but later passed medical or recreational marijuana laws assumed the higher designation. Categorical data was analyzed with chi-squared tests for descriptive statistics, logistic regression for odds of marijuana involvement, and Poisson regression for rates of positive tests and deaths. The smallest unit of data was by month and state increments in order to maximize data availability for policy implementation. Due to this, frequencies were considerably small and adjusting for lower than 1,000,000 members of the population can render the data difficult to interpret. Neither the crude frequency counts of marijuana involvement and deaths nor the adjusted per 1,000,000 counts of both variables were found to have a normal distribution. Logistic regression controlled for age, sex, race, alcohol involvement, and time measured in months, while Poisson regression controlled for state and time measured in months.The timing of legalization laws throughout the fifty states varied significantly in the time period of the analysis: some states have enacted more MPs before the start of the period (2004) than others, or had policies that did not change throughout the fifteen year duration (most commonly with states that have prohibited the use of marijuana throughout the data period). As a result, the reference category for each state (if not illegalization) was set to the lowest degree of legalization during the data period.ResultsDescriptive statistics show that the frequency of fatalities in motor vehicle transportation varied throughout the 2004-2018 year period, between a range of 10,044 deaths. The fatality count was highest in 2004 with 43,462 deaths, which then trended downward meaningfully over the years to its lowest in 2011 at 32,584 deaths. In the years following there has been a substantial increase and in 2018 there have been 42,628 fatalities reported. Overall, presence of marijuana and associated cannabinoids was only reported in 3.59% (n=45,972) of all individuals that were involved in a fatal car crash within the years of 2004-2018 in the U.S. and 76.91% (n=35,359) of the users were the driver in the accident. Among users, 78.503% (n=35,872) died during the motor vehicle accident, while 21.97% (n=10,100) survived (OR of marijuana users dying compared to non-users is 4.56, CI 4.46 – 4.65). Demographic information can be seen in Appendix A Table 2 for the characteristics of all individuals involved a fatal crash and all persons who died in the crash. Of all individuals involved in a fatal crash, 65% are reported as male and 33% as female. Among those under the influence of cannabinoids, 81% are male and 19% are female. The results of the logistic regression analysis for combined states demonstrated a clear association between increasing legalization of marijuana and the likeliness of an individual involved in a fatal car accident to have tested positive in a drug test for cannabinoids. Compared to settings where marijuana is illegal, the odds of testing positive for marijuana in both participants and drivers of fatal car crashes increases consecutively with more permissive policy as seen in Table 1 after controlling for age, sex, race, alcohol involvement and time in months. Table SEQ Table \* ARABIC 1. Odds Ratios of Testing Positive for Marijuana by Policy LevelLevel of PolicyOdds RatioLower 95% Confidence IntervalUpper 95% Confidence IntervalAll Individuals Involved in Fatal CrashesIllegal1.00----Decriminalized Only1.341.291.39Medical Legalization1.611.581.65Recreational Legalization2.332.242.42Drivers in Fatal CrashesIllegal1.00----Decriminalized Only1.281.221.34Medical Legalization1.631.591.67Recreational Legalization2.232.132.34The number of individuals who test positive for marijuana use as well as the number of MVA deaths at the national level are described in Table 2. Mean individuals refers to the average number of people in one state over the course of one month that either test positive for marijuana or die while the state is under the respective policy designation. Additionally, population adjustment occurs at the state level for that month. All results are statistically significant except for testing positive for marijuana between illegal and decriminalized states, a trend which continues at the state level and posits decriminalization policy as having the least, if any, effect on marijuana involvement and car crash deaths throughout the dataset. Generally, the average number of people who test positive for marijuana and who die in car crashes within the years of 2004-2018 increase as policy becomes more permissive except for fatalities during decriminalization, which decreases slightly. Table SEQ Table \* ARABIC 2. Marijuana Involvement and Death by Policy Level Per State Per MonthIndividuals in MVAs That Tested Positive for Marijuana InvolvementLevel of PolicyMean IndividualsP-valueMean Individuals per 1,000,000P-valueIllegal3.55<.00010.910.0053Decriminalized Only3.6<.00010.970.7703Medical Legalization4.19<.00011.160.0001Recreational Legalization5.08<.00011.35<.0001Deaths from MVAsLevel of PolicyMean IndividualsP-valueMean Individuals per 1,000,000P-valueIllegal39.64<.000110.24<.0001Decriminalized Only38.00<.000110.36<.0001Medical Legalization41.33<.000110.91<.0001Recreational Legalization50.01<.000113.55<.0001Additionally, both logistic and Poisson regression analysis was conducted within each individual state to calculate the odds of a positive marijuana test (significant results in Appendix A Table 3), the number of deaths (Appendix A Table 4) and the number of positive tests (Appendix A Table 5). However, these results differed highly in statistical significance, direction, and magnitude by state: Alaska for example saw the odds of marijuana involvement in fatal MVAs increase by 1.61 (p=0.0384, 95% CI 1.03-2.54) during the recreational legalization period as opposed to medical legalization, while Oregon saw the odds decrease from the same transition in policy by 0.53 (p=0.004, 95% CI 0.34-0.82). The odds of positive marijuana tests and number of deaths by state and by policy tended to have statistically significant results, while 35/88 changes in policy across all states were non-significant for number of positive tests. This discrepancy may be explained by the more limited availability of data by policy at the individual state level, exacerbating the already low incidence of positive tests, especially in comparison to the relatively more common car crash fatalities outcome. However, considering the highly varied confidence intervals, p-values, and imbalance of time under specific MPs or even the lack of some MPs throughout the 2004-2018 period, state-level data were less reliable. Overall, the results at the individual state level were highly irregular though most experienced an increase in fatalities from car crashes as marijuana policy became more permissive. Examples of some of the distribution of total deaths stratified by marijuana legalization and why they should be considered carefully can be seen in Appendix B Figures 1 and 2. For California (Appendix B Figure 1), which represents a state that only experienced two types of policy in the data period (2004-2018), the average number of deaths from car crashes began to rise even before the transition to recreational legalization. For Massachusetts (Appendix B Figure 2), which experienced four types of policy change, the sudden rise in fatalities in the last few months of the data period cannot be easily explained by the only two years the state had made recreational marijuana legal; furthermore, experiencing only a few years under each level of policy may not yield accurate results due to lag effects.DiscussionThe research questions posed in this project were developed to address the gaps in knowledge between traffic safety regarding marijuana use and the change in degree of marijuana legalization throughout the nation. Specifically, the objectives were aimed at investigating whether increasing legalization of marijuana was associated with marijuana involvement in fatal car crashes and total deaths from fatal car crashes. The results of this report suggest a positive association for all three outcomes: the odds of positive marijuana tests, number of positive marijuana tests and number of deaths in fatal car crashes increase with more permissive marijuana legalization. Recreational legalization has the greatest effect size for all outcomes and decriminalization has the smallest effect size, with one non-significant result at the combined state level for number of positive tests during decriminalization in comparison to positive tests during the illegal period. However, a series of factors suggest that special caution should be taken in interpreting these findings, particularly the outcome of total overall deaths from fatal car accidents by marijuana legalization. Important considerations include the often limited availability of legalization data by state, the recent trend of an increase overall in total car crash deaths over time, the contrasting directional coefficients of outcomes in different states, as well as numerous potential biases occurring throughout the original dataset.Controlling for alcohol involvement and time reduced the magnitude of results by a greater margin than controlling for sex, race, and age. Time was defined in units of months and had relatively different outcomes than measuring by year, stressing the importance of including the effective policy date in the analysis. In the overall results for the combined states, the proportion of positive tests and average number of deaths in car crashes were significantly higher for times under mMP and rMP stages. The lack of significant association during decriminalization for the odds of a positive test and for multiple outcomes at the individual state level is consistent with previous research and lends greater confidence to overall modelling. It is important to point out that these results pertain to fatal crashes only, and the findings may differ when considering less severe crashes. Crashes in the FARS database receive extensive investigation and heightened attention to impairment related issues. Non-fatal MVAs, in contrast, have by nature of the incident a limited amount of information available as they are less likely to be reported to the authorities. It is unknown whether there is a difference in representation of marijuana users among those who are involved in fatal MVAs against those who are not. Though cannabis use has been associated with some increased aggression and recklessness, these characteristics are not as widely recognized as those in other drugs such as alcohol which predisposes drivers to an increase in car crashes.While there is extensive investigation of fatal crashes, field information gathering is prone to error, drug reporting has changed over time, and drug testing policy has changed over time. The training and vigilance of law enforcement at the state level, drug testing and drug results can also be impacted as marijuana awareness and legalization increases42. Reporting issues can also influence the covariates of the analysis such as alcohol-impaired driving, which for example was either not reported or reported as unknown in nearly half the sample (Appendix A Table 2). NHTSA detailed the inconsistencies of current literature surrounding marijuana-impaired driving, the lack of standardized testing, and the comparisons to alcohol and limitations of the FARS dataset in their report to Congress in 201735. Additionally, NHTSA’s case-control crash risk study in 2015 was the first large-scale study to directly compare marijuana use in car crashes, and found that after adjusting for age, race, gender and alcohol involvement, the odds ratio disparity between marijuana users and non-marijuana users became insignificant43.The intricacies of marijuana policy pose numerous concerns for the validity of data. While policy is defined at the state level and by month of effective start date, no deliberation was given to specific clauses relating to eligibility, licensing, distribution, possession, and cultivation of cannabis. Some policy variables are more susceptible to lag (chronic consumption patterns, establishment of dispensaries and cannabis-related businesses) than others (possession and transportation amounts, ability to grow the plant at home). Medical marijuana programs can restrict eligibility depending on specific diseases or conditions44 and in states that require annual registration have been found to both lower consumption prevalence rates among youth, young adult, and lower program admission rates than states without equivalent stipulations; similarly, policy addressing home cultivation and accessibility of legal dispensaries are associated with increases in recreational and heavy use45.Other specifications of policy that can impact cannabis use patterns include the ability of states to recognize out-of-state patients for medical marijuana programs, the range of weight amounts and degree of lessened penalization that cannabis is legalized for in decriminalization laws, the amount, reach, and timeliness of authorizing dispensaries after bill approval, the date that retail sales begin, the composition percentage of THC in cannabinoid products allowed, partial decriminalization (such as for first offense) laws and potential spill-over effects onto neighboring states.Knowing that MPs are both complex and have potentially delayed effects on traffic safety, the analysis suffers additionally from states that have limited data or a narrow timeframe in which they were classified under having either illegal, decriminalization, medical marijuana, or recreationally legal MPs. Missouri for example, which had passed decriminalization laws in January 2017 and medical marijuana laws in November of 2018, has a limited number of months of data for these classifications as opposed to nearly thirteen years of data where marijuana was entirely illegal. As a result, even though the medical legalization deaths within the state were considered statistically significant, it only differs by 0.4 deaths per month per 1,000,000 from the illegalization period; for positive marijuana tests, the result is non-significant. Future studies investigating the relationship between marijuana policy and consumption trends should deliberate on specific law allowances as well as the potential bias of marijuana use in a population that must gain majority approval to pass cannabis-related laws. A state with residents that view marijuana use favorably but without political means to put cannabis laws on the ballot may have different use patterns by the time medical or recreational marijuana is legalized compared to a state unreceptive to cannabis.Finally, it is important to consider not only seen factors that may influence marijuana legalization on its involvement in fatal car crashes and overall deaths, but unseen factors that may directly and indirectly affect the outcomes of study. After bearing in mind the biases of the dataset used and the complexity of legalization policy, the trends of traffic accidents in general over time should be examined more closely. Deaths from fatal car crashes can stem from inclement weather, need of the public to travel more distance, risk taking behaviors among drivers, road infrastructure, eyesight, advancements in technology and educational awareness among an enormous variety of other causes46. Without proper understanding of these factors, investigating and interpreting traffic safety outcomes will continue to be elusive, but the apparent reemergence of fatal car deaths and its historical importance as an obstacle to public health will need to be addressed.TablesAppendix A Table 1. Marijuana Laws by State (August 2020)StateType of lawAge restrictionsPossession limitsRetail recreational sales allowedAlabamalimited medical; effective July 1, 2014nonespecified cannabis product that contains no more than 3 percent THC?Alaskamedical; effective June 1, 1999noneno more than 1 ounce?recreational; effective February 24, 2015if under age 21, not allowed to purchase, possess, or useno more than 1 ounceOct-16Arizonamedicalnoneno more than 2.5 ounces?Arkansasmedical; effective November 9, 2016if under age 21, cannot smoke medical marijuanano more than 2.5 ounces?Californiamedical; effective November 6, 1996noneno more than 8 ounces unless a greater amount is deemed medically necessary?recreational; effective November 9, 2016if under age 21, not allowed to purchase, possess, or useno more than 28.5 grams of cannabis not in the form of concentrated cannabis and no more than 8 grams of concentrated cannabis1-Jan-18Coloradomedical; effective June 1, 2001if under age 18, cannot smoke medical marijuana when on school grounds, on a school bus, or at a school-sponsored eventno more than 2 ounces unless a greater amount is deemed medically necessary?recreational; effective December 10, 2012if under age 21, not allowed to purchase, possess, or useno more than 1 ounce1-Jan-14-44450-439420Appendix A Table 1 Continued00Appendix A Table 1 ContinuedConnecticutmedical; effective October 1, 2012if under age 21, cannot smoke medical marijuananot to exceed an amount reasonably necessary to ensure the uninterrupted availability for 1 month?Delawaremedical; effective July 1, 2011if under age 18, may use only medical marijuana oil and only for certain debilitating conditions and symptomsno more than 6 ounces?District of Columbiamedical; effective in 2009noneno more than 4 ounces?recreational; effective February 26, 2015if under age 21, not allowed to purchase, possess, or useno more than 2 ouncesnot allowedFloridamedical; effective March 25, 2016none70-day supply or 4 ounces in a form for smoking unless a greater amount is deemed medically necessary?Georgialimited medical; April 16, 2015noneno more than 20 fluid ounces of specified cannabis product that contains no more than 5 percent THC?Hawaiimedical; effective June 14, 2000noneno more than 4 ounces?Idahono lawn/an/a?Illinoismedical; effective January 1, 2014if under age 18, may have ID card only for seizures or as provided by administrative rule; if under age 21, may use only medical cannabis-infused productsno more than 2.5 ounces unless a greater amount is deemed medically necessary; for registered qualifying patients who are at least 21 years old, 5 plants that are more than 5 inches tall and any cannabis produced by those plants so long as any amount in excess of 30 grams of raw cannabis is secure within the residence?recreational; effective January 1, 2020if under age 21, not allowed to purchase, possess, or useno more than 30 ounces of cannabis flower, 500 milligrams of THC contained in cannabis-infused product, and 5 grams of cannabis concentration1-Jan-20Indianalimited medical; April 26, 2017nonespecified cannabis product that contains no more than 0.3 percent THC?Iowalimited medical; effective July 1, 2014noneno more than 4.5 grams in a 90-day period unless a greater amount is deemed medically necessary?-44450-420370Appendix A Table 1 Continued00Appendix A Table 1 ContinuedKansaslimited medical; effective July 1, 2019nonespecified cannabis product that contains no more than 5 percent THC relative to the cannabidiol concentration in the preparation?Kentuckylimited medical; effective April 10, 2014nonespecified cannabis product obtained pursuant to a written order of a physician practicing at a hospital or associated clinic affiliated with a Kentucky public university having a college or school of medicine, derived from industrial hemp, or approved as a prescription by the FDA?Louisianalimited medicalnone1 month supply; one dose shall contain no more than 10 milligrams of THC?Mainemedical; December 22, 1999noneup to 2.5 ounces?recreational; effective January 30, 2017if under age 21, not allowed to purchase, possess, or useup to 2.5 ouncesexpected in March 2020Marylandmedical; effective June 1, 2011noneno more than 30-day supply unless a greater amount is deemed medically necessary?Massachusettsmedical; effective January 1, 2013noneno more than 60-day supply, up to 10 ounces or as determined by the cannabis control commission?recreational; effective December 15, 2016if under age 21, not allowed to purchase, possess, or useno more than 1 ounce; within the person's primary residence, no more than 10 ounces20-Nov-18Michiganmedical; effective December 4, 2008noneno more than 2.5 ounces?recreational; effective December 6, 2018if under age 21, not allowed to purchase, possess, or useno more than 2.5 ounces; within the person's residence, no more than 10 ounces1-Dec-19Minnesotamedical; effective May 30, 2014noneno more than 30-day supply?Mississippilimited medical; effective April 17, 2014nonespecified cannabis product provided by the National Center for Natural Products Research at the University of Mississippi and dispensed by the Department of Pharmacy Services at the University of Mississippi Medical Center?Missourimedical; effective December 6, 2018if under age 18 and not emancipated, may not have an ID card, purchase, or possess marijuanapurchase no more than 30-day supply, which can be limited to no less than 4 ounces of dried, unprocessed marijuana, unless a greater amount is deemed medically necessary; possess at least 60-day supply, although qualifying patients who can cultivate marijuana may possess up to 90-day supply?-44450-1349375Appendix A Table 1 Continued00Appendix A Table 1 ContinuedMontanamedical; effective November 2, 2004if under age 18, cannot smoke medical marijuana and can only used marijuana-infused productsup to 1 ounce?Nebraskano lawn/an/a?Nevadamedical; effective by late November or early December 2000noneno more than 2.5 ounces in any 14-day period unless a greater amount is deemed medically necessary?recreational; effective January 1, 2017if under age 21, not allowed to purchase, possess, or useno more than 1 ounce1-Jul-17New Hampshiremedical; effective July 23, 2013noneno more than 2 ounces?New Jerseymedical; effective October 1, 2010noneno more than 3 ounces in a 30-day period unless a greater amount is deemed medically necessary?New Mexicomedical; effective July 1, 2007none3-month supply?New Yorkmedical; effective July 5, 2014noneno more than 30-day supply; individual dose may not contain more than 10 milligrams of THC?North Carolinalimited medical; effective July 13, 2014nonespecified cannabis product that contains no more than 0.9 percent THC?North Dakotamedical; effective April 17, 2017if under age 19, may use only "pediatric medical marijuana", which contains no more than 6 percent THCno more than 3 ounces unless an amount up to 7.5 ounces is deemed medically necessary?Ohiomedical; effective September 8, 2016noneno more than 90-day supply?Oklahomamedical; effective July 26, 2018noneno more than 72 ounces of edible marijuana, 3 ounces of marijuana on the person, 8 ounces of marijuana in the residence, and 1 ounce of concentrated marijuana?-44450-762000Appendix A Table 1 Continued00Appendix A Table 1 ContinuedOregonmedical; effective December 3, 1998if under age 18, cannot produce medical marijuanano more than 24 ounces?recreational; effective December 4, 2014if under age 21, not allowed to purchase, possess, or useno more than 8 ounces of usable marijuana, 16 ounces of cannabinoid products in solid form, 72 ounces of cannabinoid products in liquid form, and 16 ounces of cannabinoid concentrates1-Oct-15Pennsylvaniamedical; effective May 17, 2016noneno more than 30-day supply?Rhode Islandmedical; effective July 1, 2006noneno more than 2.5 ounces and an amount of wet marijuana as determined by the departments of health and business regulation?South Carolinalimited medical; effective June 2, 2014nonespecified cannabis product that contains no more than 0.9 percent THC?South Dakotano lawn/an/a?Tennesseelimited medical; effective May 16, 2014nonespecified cannabis product that contains less than 0.9 percent THC?Texaslimited medical; effective June 1, 2015nonespecified cannabis product that contains no more than 0.5 percent THC?Utahmedical; effective May 8, 2018if under age 18, may only qualify for a provisional patient cardlegal dosage limit sufficient to provide 30 days of treatment and may not exceed 113 grams of unprocessed marijuana or an amount of cannabis product that contains no more than 20 grams of total composite THC?Vermontmedical; effective July 1, 2004noneno more than 2 ounces?recreational; effective July 1, 2018if under age 21, not allowed to purchase, possess, or useno more than 1 ouncenot allowedVirginialimited medical; effective February 26, 2015nonespecified cannabis product that contains no more than 5 percent THC?Washingtonmedical; December 3, 1998if under age 18, may not grow marijuana plants or purchase marijuana-infused products, useable marijuana, or marijuana concentrates from a marijuana retailerno more than 48 ounces of marijuana-infused product in solid form, 3 ounces of useable marijuana, 216 ounces of marijuana-infused product in liquid form, or 21 grams of marijuana concentrates unless a greater amount is deemed medically necessary,?recreational; effective December 6, 2012if under age 21, not allowed to purchase, possess, or useno more than 1 ounce of useable marijuana, 16 ounces of marijuana-infused product in solid form; 72 ounces of marijuana-infused product in liquid form, and 7 grams of marijuana concentrate8-Jul-14West Virginiamedical; effective July 1, 2019noneno more than 30-day supply?Wisconsinlimited medical; effective April 17, 2014nonespecified cannabis product in a form without a psychoactive effect?Wyominglimited medical; effective July 1, 2015nonespecified cannabis product that contains less than 0.3 percent THC?left-2595880Appendix A Table 1 Continued00Appendix A Table 1 ContinuedAppendix A Table 2. Demographics of Individuals Involved in Car CrashesVariableCategoryFrequency (Percent)Individuals in All Crashes (n=1,280,256)Age???0-1282002 (6.41%)?13-1781520 (6.37%)?18-25262567 (20.51%)?26-35214711 (16.77%)?36-45179364 (14.01%)?46-55171875 (13.43%)?56-65124602 (9.73%)?65+163615 (12.78%)Sex???Male837071 (65.38%)?Female423902 (33.11%)Marijuana Involvement???Yes45972 (3.59%)?No1234284 (96.41%)Alcohol Involvement???Yes135713 (10.6%)?No515887 (40.3%)?Not Reported498706 (38.95%)?Reported as Unknown129950 (10.15%)Individuals in Fatal Crashes (n=569,905)Age???0-1216489 (2.94%)?13-1725604 (4.56%)?18-25111300 (19.84%)?26-3593136 (16.60%)?36-4579090 (14.10%)?46-5582983 (14.79%)?56-6564583 (11.51%)?65+87720 (15.64%)Sex???Male395424 (70.5%)?Female165206 (29.45%)?Unknown or Other275 (0.04%)Marijuana Involvement???No525033 (93.6%)?Yes35872 (6.4%)Alcohol Involvement???Yes91390 (16.29%)?No193911 (34.57%)?Not Reported175604 (31.31%)?Reported as Unknown100000 (17.83%)Race???White408496 (72.8%)?Black68113 (12.1%)?American Indian (includes Alaska Native)9277 (1.7%)?Asian8131 (1.4%)?Multiple Races1401 (0.2%)?Pacific Islander4262 (0.8%)?Unknown or Other61225 (10.9%)left-4564380Appendix A Table 2 Continued00Appendix A Table 2 Continued-19050-5972810Appendix Table 1 Continued00Appendix Table 1 ContinuedAppendix A Table 3. Significant Odds Ratios of Marijuana Involvement by StateStatePolicy ComparisonOdds RatioLower 95% Confidence IntervalUpper 95% Confidence IntervalP-valueAlaskaRecreational Legalization vs Medical Legalization1.611.032.540.038ConnecticutMedical Legalization vs Decriminalized Only0.160.040.660.011ConnecticutIllegal vs Decriminalized Only0.210.050.890.034FloridaMedical Legalization vs Illegal0.810.710.920.001LouisianaMedical Legalization vs Illegal0.500.380.65<0.0001MassachusettsMedical Legalization vs Decriminalized Only1.471.052.070.0264MichiganRecreational Legalization vs Illegal0.510.390.67<0.0001MichiganMedical Legalization vs Illegal0.560.440.72<0.0001OklahomaMedical Legalization vs Illegal0.600.390.920.020OregonRecreational Legalization vs Medical Legalization0.530.340.820.004Appendix A Table 4. Deaths in Car Crashes per Month by State and Policy Level Adjusted per 1,000,000StatePolicy LevelDeathsP-value*StatePolicy LevelDeathsP-value*AlabamaIllegal17.2282<.0001MissouriDecriminalized Only17.7164<.0001AlaskaMedical Legalization7.7881<.0001MissouriMedical Legalization17.2716<.0001AlaskaRecreational Legalization11.8054<.0001MontanaIllegal16.9616<.0001ArizonaIllegal13.1031<.0001MontanaMedical Legalization18.5712<.0001ArizonaMedical Legalization12.0313<.0001NebraskaDecriminalized Only10.3855<.0001ArkansasIllegal16.6308<.0001NevadaMedical Legalization9.471<.0001ArkansasMedical Legalization17.1561<.0001NevadaRecreational Legalization13.3362<.0001CaliforniaMedical Legalization7.466<.0001New HampshireIllegal7.3518<.0001CaliforniaRecreational Legalization10.3538<.0001New HampshireMedical Legalization9.6953<.0001ColoradoMedical Legalization8.4394<.0001New JerseyIllegal6.6637<.0001ColoradoRecreational Legalization9.949<.0001New JerseyMedical Legalization5.5899<.0001ConnecticutIllegal6.7813<.0001New MexicoIllegal21.1129<.0001ConnecticutDecriminalized Only5.8169<.0001New MexicoMedical Legalization14.8906<.0001ConnecticutMedical Legalization6.6288<.0001New YorkIllegal5.0858<.0001DelawareIllegal11.3817<.0001New YorkMedical Legalization5.3793<.0001DelawareMedical Legalization11.019<.0001North CarolinaIllegal12.3275<.0001FloridaIllegal12.0695<.0001North DakotaIllegal15.6262<.0001FloridaMedical Legalization16.147<.0001North DakotaMedical Legalization14.162<.0001GeorgiaIllegal12.3732<.0001OhioDecriminalized Only8.0278<.0001HawaiiMedical Legalization7.2928<.0001OhioMedical Legalization11.5922<.0001IdahoIllegal12.2585<.0001OklahomaIllegal15.7489<.0001IllinoisIllegal6.6491<.0001OklahomaMedical Legalization19.364<.0001IllinoisMedical Legalization7.9816<.0001OregonMedical Legalization8.0477<.0001IndianaIllegal10.6858<.0001OregonRecreational Legalization13.2238<.0001IowaIllegal10.2217<.0001PennsylvaniaIllegal8.5987<.0001KansasIllegal12.1011<.0001PennsylvaniaMedical Legalization9.932<.0001KentuckyIllegal15.8228<.0001Rhode IslandIllegal6.1742<.0001LouisianaIllegal14.2944<.0001Rhode IslandMedical Legalization5.3361<.0001LouisianaMedical Legalization18.3227<.0001South CarolinaIllegal17.077<.0001MaineMedical Legalization9.8215<.0001South DakotaIllegal14.4332<.0001MaineRecreational Legalization12.5655<.0001TennesseeIllegal14.3094<.0001MarylandIllegal7.343<.0001TexasIllegal11.4404<.0001MarylandMedical Legalization9.2981<.0001UtahIllegal8.0099<.0001MassachusettsIllegal5.9169<.0001UtahMedical Legalization4.48790.0035MassachusettsDecriminalized Only4.6263<.0001VermontIllegal6.6028<.0001MassachusettsMedical Legalization4.2281<.0001VermontMedical Legalization9.3799<.0001MassachusettsRecreational Legalization5.0778<.0001VermontRecreational Legalization16.6773<.0001MichiganIllegal10.5254<.0001VirginiaIllegal8.6222<.0001MichiganMedical Legalization7.6477<.0001WashingtonMedical Legalization6.2905<.0001MichiganRecreational Legalization8.8059<.0001WashingtonRecreational Legalization7.0118<.0001MinnesotaDecriminalized Only6.3191<.0001West VirginiaIllegal15.2915<.0001MinnesotaMedical Legalization7.732<.0001West VirginiaMedical Legalization21.2393<.0001MississippiDecriminalized Only20.4965<.0001WisconsinIllegal9.4016<.0001MissouriIllegal12.5247<.0001WyomingIllegal21.1952<.0001left-3371215Appendix A Table 4 Continued00Appendix A Table 4 ContinuedAppendix A Table 5. Marijuana Involvement in Car Crashes per Month by State and Policy Level Adjusted per 1,000,000StatePolicy LevelPositive TestsP-valueStatePolicy LevelPositive TestsP-valueAlabamaIllegal1.14280.1195MissouriDecriminalized Only1.94310.0002AlaskaMedical Legalization2.7628<.0001MissouriMedical Legalization1.60480.3554AlaskaRecreational Legalization3.3883<.0001MontanaIllegal2.8833<.0001ArizonaIllegal0.85460.4766MontanaMedical Legalization3.5318<.0001ArizonaMedical Legalization0.61860.0093NebraskaDecriminalized Only0.80970.0617ArkansasIllegal1.5826<.0001NevadaMedical Legalization1.4137<.0001ArkansasMedical Legalization1.66970.1589NevadaRecreational Legalization2.1657<.0001CaliforniaMedical Legalization0.90880.2714New HampshireIllegal1.7421<.0001CaliforniaRecreational Legalization1.26310.2788New HampshireMedical Legalization2.1968<.0001ColoradoMedical Legalization1.0710.6137New JerseyIllegal0.69660.1673ColoradoRecreational Legalization1.18490.3279New JerseyMedical Legalization0.52220.0006ConnecticutIllegal1.36990.5172New MexicoIllegal2.70460.0296ConnecticutDecriminalized Only0.39480.4893New MexicoMedical Legalization1.5971<.0001ConnecticutMedical Legalization0.62910.0788New YorkIllegal0.5371<.0001DelawareIllegal1.91760.0023New YorkMedical Legalization0.56030.0309DelawareMedical Legalization1.901<.0001North CarolinaIllegal0.12010.0063FloridaIllegal0.6113<.0001North DakotaIllegal1.9779<.0001FloridaMedical Legalization1.00710.9783North DakotaMedical Legalization1.40710.2913GeorgiaIllegal0.70010.0001OhioDecriminalized Only1.13620.0904HawaiiMedical Legalization1.7518<.0001OhioMedical Legalization1.79770.0021IdahoIllegal1.20790.028OklahomaIllegal0.4614<.0001IllinoisIllegal0.89540.4426OklahomaMedical Legalization0.94480.8917IllinoisMedical Legalization0.84530.4033OregonMedical Legalization0.4682<.0001IndianaIllegal0.87860.1101OregonRecreational Legalization0.80260.4974IowaIllegal0.6104<.0001PennsylvaniaIllegal0.5762<.0001KansasIllegal0.78780.0079PennsylvaniaMedical Legalization0.73390.2586KentuckyIllegal1.24040.0034Rhode IslandIllegal1.52230.2575LouisianaIllegal0.63050.0004Rhode IslandMedical Legalization1.6031<.0001LouisianaMedical Legalization1.53650.0475South CarolinaIllegal2.1293<.0001MaineMedical Legalization0.94850.8115South DakotaIllegal1.807<.0001MaineRecreational Legalization0.64760.3666TennesseeIllegal1.03110.6849MarylandIllegal0.20380.0078TexasIllegal0.5541<.0001MarylandMedical Legalization0.1780.2476UtahIllegal0.70920.0019MassachusettsIllegal1.09930.8564UtahMedical Legalization0.3850.4514MassachusettsDecriminalized Only0.77520.2419VermontIllegal2.34860.0677MassachusettsMedical Legalization0.4570.0134VermontMedical Legalization2.7285<.0001MassachusettsRecreational Legalization0.49670.2096VermontRecreational Legalization3.1222<.0001MichiganIllegal0.5710.0662VirginiaIllegal0.4849<.0001MichiganMedical Legalization0.69410.012WashingtonMedical Legalization1.3190.0209MichiganRecreational Legalization0.91710.8094WashingtonRecreational Legalization1.47590.0137MinnesotaDecriminalized Only0.4409<.0001West VirginiaIllegal1.3962<.0001MinnesotaMedical Legalization0.59060.0701West VirginiaMedical Legalization1.79360.0539MississippiDecriminalized Only0.88310.3028WisconsinIllegal0.97960.8006MissouriIllegal1.508<.0001WyomingIllegal3.3191<.0001left-3383915Appendix A Table 5 Continued00Appendix A Table 5 ContinuedFiguresAppendix B Figure SEQ Appendix_Figure \* ARABIC 1. 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Does Vermont have legal marijuana? Yes, both adult-use and medical marijuana are legal in Vermont, though recreational sales are not yet operational. Vermont legalized marijuana for medicinal use in 2004 when the state legislature passed S 76, An Act Relating to the Medical Use of Marijuana.