Position Statement on Cannabis

Statement of concern

We have become concerned about the high rates of cannabis use among young people in Marin. A substantial body of research shows that when youth under the age of 26 use cannabis frequently or heavily for “recreational” purposes, they can experience a wide range of adverse effects, including altered brain development, impaired decision-making, poor academic performance, diminished life satisfaction, cannabis dependence and addiction, and other mental health problems.1–3

Various terms are used, sometimes interchangeably, in discussing this issue. For the purposes of this document, we use the term “cannabis” to mean all products containing THC that users smoke, vape, otherwise inhale, eat and drink. We use the term “marijuana” to refer to cannabis plant material that is smoked.  

Our position

Youth: We think our communities in Marin should be undertaking efforts to ensure that youth under the age of 21 do not use cannabis, unless under the direction of a healthcare provider for medical purposes for which cannabis has been scientifically demonstrated to provide therapeutic benefits.

Young adults: Although young adults in California can legally consume cannabis at age 21, we also recommend that our communities undertake efforts to prevent young adults from using cannabis products and work to reduce use among young adults, unless under the direction of a healthcare provider for medical purposes for which cannabis has been scientifically demonstrated to provide therapeutic benefits.

Background and scientific evidence

California’s Proposition 64 – the Control, Regulate and Tax Adult Use of Marijuana Act (“AUMA”) – legalized adult cannabis use and possession in 2016. Before Prop 64 was presented to the voters, Marin had some of the highest rates of youth use in the state. In 2015-16, compared to 9th graders in California, the rate of current use of cannabis among 9th graders in Marin was 23% higher, and among 11th graders it was 50% higher. At some high schools in Marin, current cannabis use among 9th graders was up to 46% higher, and among 11th graders 130% higher, where nearly half of 11th graders were current users. In Marin’s nontraditional high schools, up to 79% of students were current cannabis users.4

There are reasons why many of Marin’s teens have been smoking, vaping, eating and drinking cannabis at high rates. Marin County has a long history of widespread marijuana use and cultivation. Over several decades, marijuana use among teens and adults became commonplace, meaning that communities in Marin have developed social norms that allow for widespread acceptance and use of cannabis.

A great deal is still unknown about the health effects of cannabis use. Some rigorous scientific research has shown that using cannabis for some specific medical conditions provides medical benefits that outweigh the risks.5 We are not opposed to the availability of cannabis for medicinal purposes, as allowed by California law under the Compassionate Use Act (passed in 1996) and the Medical Marijuana Regulation and Safety Act (MMRSA).6 These laws provide for individuals 18 years and older who have a prescription for medical cannabis use for legitimate reasons to treat specific medical conditions for which medical cannabis has been shown to be effective, provided that medical cannabis is being used in legally permitted locations (see below).

Scientific research has identified a range of adverse effects of marijuana use strongly associated with initial use of marijuana in adolescence and young adulthood.1–3 These include, altered brain development, addiction, serious mental health problems, cognitive impairment, poor educational outcomes, increased likelihood of dropping out of school, and diminished life satisfaction and achievement based on subjective and objective measures.1,3

In 2016, Prop 64 passed in California by 57.1%, and in Marin by 69.6%.7,8 In voting for Prop 64, the majority of California voters recognized in the proposed language of the law that cannabis use should be decriminalized, and that use should be restricted to adults because cannabis use presents public health risks and safety hazards for young people. California law does not legalize cannabis use for everyone, the possession and growing of any amount, or use everywhere.

As of January 2018, it remains illegal for youth under the age of 21 to use, possess or grow cannabis products.9 California law allows for adults ages 21 and older to use cannabis in private homes, and in businesses licensed for on-site cannabis consumption. Adults are allowed to possess up to 28.5 grams of marijuana (about one ounce) and 8 grams (0.28 ounces) of concentrated cannabis. It remains illegal to possess cannabis on school grounds, at day care centers, and in youth centers.

The law allows adults to grow up to six plants inside a private home for personal consumption.9 Some local jurisdictions have passed ordinances that allow growing of the maximum number of six plants outdoors in private yards, as long as they are in a locked area and not visible from a public place. 

Because smoking and vaping cannabis produces harmful secondhand smoke and secondhand aerosol, it is illegal to smoke or vape cannabis anywhere tobacco smoking and vaping of nicotine is prohibited by California State or local laws, including at all schools, in or near all government buildings, in all public transportation, at most workplaces, in common areas in apartment buildings and condominiums, within 250 ft of recreational facilities, and in or near children’s playgrounds and farmers’ markets.9,10

Additionally, because evidence has shown that cannabis use impairs judgment and can cause accidents, using cannabis while driving a motorized vehicle remains illegal.9,11–14

We agree that legalization under Prop 64 has addressed social inequities in the criminalization of marijuana use and possession. Thousands of lives were destroyed by unnecessary prosecution and jail sentences. Prop 64 reduced the offense degree for numerous state statutes, further contributing to reducing unnecessary costs to California taxpayers in the criminal justice system for marijuana offenses.15–17

Specific areas of concern

With legalization of adult use, we have seen a rapid proliferation of a powerful burgeoning cannabis industry. We have become increasingly concerned about the wide range of cannabis products being marketed by this industry, particularly the high potency products with THC levels between 15-60%18 and even with concentrations reaching as high as 99%.19 New generations of cannabis products are designed to target youth with catchy names, flavors and convenient stealthy devices. With legalization, Big Tobacco companies like Altria (Phillip Morris) have invested billions of dollars in the cannabis industry.20 Accordingly, counties and cities throughout California, including the County of Marin and many other jurisdictions throughout Marin County have passed ordinances regulating legal cannabis businesses and growing for personal use.21

Cannabis is now readily available in many forms that young people in Marin are using, including flower (also known as “weed” or “buds”), vaping concentrates, hash oil for dabbing, edibles, candies, beverages and tinctures. Today, most of these products have THC potency levels far stronger than the levels of marijuana available at the time voters considered Prop 64.18 Increased availability of high-potency products can reinforce a perception among youth that these products are safe and can be used for “recreational” fun without adverse effects.22

For these reasons, and the evidence below, we believe our communities in Marin should be undertaking efforts to ensure that youth and young adults do not use cannabis products.

Justifications for call to action:

  1. Cognitive impairment: consistent cannabis use has been associated with neuropsychological decline broadly across domains of functioning, even after controlling for years of education.23
  2. Addiction: Initiation of cannabis use in adolescence can cause increased risk of physical dependence, high addiction potential and other negative consequences. Addiction occurs in about 9% of users overall, 17% of those who begin use in adolescence, and 25% or more among those who are daily users.1–3 The use of high-potency cannabis has been shown to be strongly associated with increased severity of dependence.24
  3. Mental health: Cannabis use has been linked to increased mental illness, including depression, anxiety, and psychosis among adolescents.1–3
  4. Suicide: Adolescents who use cannabis are more likely to make suicide attempts.25
  5. Poor academic performance: adolescents who use cannabis regularly are more likely to have school absences and drop out from school.1,3
  6. Lack of motivation: regular cannabis users are more likely experience amotivational disorder, meaning that they lack the will to undertake activities that would benefit them in life.26
  7. Diminished life satisfaction and achievement: cannabis users are at higher risk of struggling in life, including lower income, greater need for socioeconomic assistance, unemployment, engaging in criminal behavior, and lower self-rated satisfaction with life.1,3
  8. Other drug use: frequent use of cannabis by adolescents showed a 130% greater likelihood of misusing opioids.27,28 Early initiation of marijuana is a dominant predictor of Opioid Use Disorder.
  9. Poisonings: edible cannabis products like gummies and candies have increased the risk of unintentional overdose, as well as accidental ingestion by children and adolescents.29,30
  10. Motor vehicle safety and accidents: cannabis use increases the risk of motor vehicle accidents.11–13 Since recreational use was legalized in Washington State, the percentage of THC-positive drivers has doubled, and cannabis-related accidents have increased.12

Recommendations for action:

  • Do not allow the wholesale or retail sale of non-medical cannabis products in our communities.
  • Establish a panel of public health experts, addiction-certified healthcare providers, prevention and treatment professionals, educators and others knowledgeable about cannabis use to provide ongoing policy recommendations on local cannabis policies.
  • Follow the recommendations of the Center for Disease Control and Prevention, California Department of Public Health and American Lung Association.
  • Request that the Marin Civil Grand Jury conduct an investigation into the issue of youth cannabis use in Marin and prepare a report with recommendations.


1.             Volkow ND, Baler RD, Compton WM, Weiss SRB. Adverse health effects of marijuana use. N Engl J Med. 2014;370(23):2219-2227. doi:10.1056/NEJMra1402309

2.             National Academies of Sciences, Engineering and Medicine. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. The National Academies Press; 2017. https://www.nap.edu/catalog/24625/the-health-effects-of-cannabis-and-cannabinoids-the-current-state

3.             George T, Vaccarino F. Substance Abuse in Canada: The Effects of Cannabis Use during Adolescence. Canadian Centre on Substance Abuse; 2015. https://www.ccsa.ca/effects-cannabis-use-during-adolescence-report

4.             WestEd. California Healthy Kids Survey, Marin County, 2015-16.; 2017.

5.             Inglet S, Winter B, Yost SE, et al. Clinical Data for the Use of Cannabis-Based Treatments: A Comprehensive Review of the Literature. Ann Pharmacother. Published online June 2, 2020:1060028020930189. doi:10.1177/1060028020930189

6.             California Legislature. Uniform Controlled Substances Act: Medical Marijuana Program. Vol 11357-11362.9. https://leginfo.legislature.ca.gov/faces/codes_displayText.xhtml?division=10.&chapter=6.&lawCode=HSC&article=2.5.

7.             Ballotpedia: The Encyclopedia of American Politics. California Proposition 64, Marijuana Legalization (2016). Accessed June 9, 2020. https://ballotpedia.org/California_Proposition_64,_Marijuana_Legalization_(2016)

8.             Elections Department. County of Marin – Elections – November 8, 2016 General Election Results. Accessed June 9, 2020. https://www.marincounty.org/depts/rv/election-info/past-elections/page-data/tabs-collection/past2016/nov-8/results

9.             California Legislature. Uniform Controlled Substances Act: Cannabis. Vol 11357-11362.9. https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=HSC&sectionNum=11362.3.

10.             California Legislature. Disease Prevention and Health Promotion. Vol 104350-104559. https://leginfo.legislature.ca.gov/faces/codes_displayText.xhtml?division=103.&chapter=1.&part=3.&lawCode=HSC&article=1.

11.             Asbridge M, Hayden JA, Cartwright JL. Acute cannabis consumption and motor vehicle collision risk: systematic review of observational studies and meta-analysis. BMJ. 2012;344:e536. doi:10.1136/bmj.e536

12.             American Automobile Association. Fatal Crashes Involving Drivers Who Test Positive for Marijuana Increase After State Legalizes Drug. AAA NewsRoom. Published January 30, 2020. Accessed June 9, 2020. https://newsroom.aaa.com/2020/01/fatal-crashes-involving-drivers-who-test-positive-for-marijuana-increase-after-state-legalizes-drug/

13.             Kamer RS, Warshafsky S, Kamer GC. Change in Traffic Fatality Rates in the First 4 States to Legalize Recreational Marijuana. JAMA Intern Med. Published online 2020. https://doi.org/10.1001/jamainternmed.2020.1769

14.             California Legislature. Offenses Involving Alcohol and Drugs. Vol 23152-23229.1. https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH&sectionNum=23222.&article=2.&highlight=true&keyword=cannabis+vehicle

15.             Caulkins JP. Cost of Marijuana Prohibition on the California Criminal Justice System. Published online 2010:17.

16.             New Frontier Data. Marijuana Incarcerations in California Jails.; 2016. Accessed June 9, 2020. https://www.drugpolicy.org/sites/default/files/NF-DPA-California-Incarcerations-Report-2016-FINAL.pdf

17.             California Department of Justice. Crime in California 2018.; 2019. https://data-openjustice.doj.ca.gov/sites/default/files/2019-07/Crime%20In%20CA%202018%2020190701.pdf

18.             Cash MC, Cunnane K, Fan C, Romero-Sandoval EA. Mapping cannabis potency in medical and recreational programs in the United States. PLoS ONE. 2020;15(3). doi:10.1371/journal.pone.0230167

19.             Bennett P. Cannabis oil distillate concentrate: pure THC. Leafly. Published online June 26, 2020. Accessed July 6, 2020. https://www.leafly.com/news/science-tech/what-are-cannabis-distillate-concentrates

20.             Altria Group, Inc. Annual Report.; 2019. http://investor.altria.com/Cache/IRCache/eddd2295-4dc4-c83d-5b11-45594ea5c570.PDF?O=PDF&T=&Y=&D=&FID=eddd2295-4dc4-c83d-5b11-45594ea5c570&iid=4087349

21.             Silver LD, Naprawa AZ, Padon AA. Assessment of Incorporation of Lessons From Tobacco Control in City and County Laws Regulating Legal Marijuana in California. JAMA Netw Open. 2020;3(6):e208393-e208393. doi:10.1001/jamanetworkopen.2020.8393

22.             National Institute on Drug Abuse. Monitoring the Future Survey: High School and Youth Trends DrugFacts. National Institute on Drug Abuse; 2020. Accessed June 6, 2020. https://www.drugabuse.gov/publications/drugfacts/monitoring-future-survey-high-school-youth-trends

23.             Meier MH, Caspi A, Ambler A, et al. Persistent cannabis users show neuropsychological decline from childhood to midlife. Proc Natl Acad Sci U S A. 2012;109(40):E2657-2664. doi:10.1073/pnas.1206820109

24.             Freeman TP, Winstock AR. Examining the profile of high-potency cannabis and its association with severity of cannabis dependence. Psychol Med. 2015;45(15):3181-3189. doi:10.1017/S0033291715001178

25.             Lopez-Quintero C, Pérez de los Cobos J, Hasin DS, et al. Probability and predictors of transition from first use to dependence on nicotine, alcohol, cannabis, and cocaine: results of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Drug Alcohol Depend. 2011;115(1-2):120-130. doi:10.1016/j.drugalcdep.2010.11.004

26.             Petrucci AS, LaFrance EM, Cuttler C. A Comprehensive Examination of the Links between Cannabis Use and Motivation. Subst Use Misuse. 2020;55(7):1155-1164. doi:10.1080/10826084.2020.1729203

27.             Jones CM, McCance-Katz EF. Relationship Between Recency and Frequency of Youth Cannabis Use on Other Substance Use. J Adolesc Health Off Publ Soc Adolesc Med. 2019;64(3):411-413. doi:10.1016/j.jadohealth.2018.09.017

28.             Wadekar AS. Understanding Opioid Use Disorder (OUD) using tree-based classifiers. Drug Alcohol Depend. 2020;208:107839. doi:10.1016/j.drugalcdep.2020.107839

29.             Richards JR, Smith NE, Moulin AK. Unintentional Cannabis Ingestion in Children: A Systematic Review. J Pediatr. 2017;190:142-152. doi:10.1016/j.jpeds.2017.07.005

30.             Cao D, Srisuma S, Bronstein AC, Hoyte CO. Characterization of edible marijuana product exposures reported to United States poison centers. Clin Toxicol Phila Pa. 2016;54(9):840-846. doi:10.1080/15563650.2016.1209761