Assessing the relationship between marijuana availability and marijuana use: a legal and sociological comparison between the United States and the Netherlands.

Abstract

The United States and the Netherlands have antithetical marijuana control policies. The United States' laws criminalize the possession of even small amounts of marijuana, while the Netherlands have maintained, over the past several decades, two relatively liberal marijuana policies implemented during the 1970s and 1980s. According to the literature on environmental drug prevention strategies, the Dutch policy should result in increased marijuana use because of the drug's amplified availability, while the United States 'policy should result in reduced marijuana use. The empirical evidence addressing these hypotheses, however, is sparse.

The stark approaches to marijuana control in the United States and the Netherlands offer the opportunity for an intricate legal and social science analysis. An examination of these divergent policies is important because it implicates, first, the extent to which marijuana, a relatively non-serious drug of abuse, is controlled, and second, the extent to which environmental drug prevention strategies are realized by policymakers in the United States and in the Netherlands. Part I of this essay examines the short- and long-term physical and psychological effects of marijuana use. Part II, first, summarizes the marijuana control philosophy in the United States, and second, examines the prevalence of marijuana use in the United States. Part III first, summarizes the Dutch philosophy on marijuana control, and second, reviews the prevalence of marijuana use in the Netherlands. Part IV discusses the implications of the American and Dutch marijuana control policies in relation to environmental drug prevention strategies.

MARIJUANA

Marijuana is a greenish-gray mixture of the dried, shredded leaves, stems, seeds, and flowers of Cannabis sativa, the hemp plant (El Sohly et al., 2000). The major active chemical in marijuana is delta-9-tetrahydrocannabinol (THC), which causes the mind-altering effects of marijuana intoxication. The amount of THC determines the potency and, thereby, the effects of marijuana (El Sohly et al., 2000).

Acute Effects of Marijuana

When someone smokes marijuana, THC rapidly passes from the lungs into the bloodstream, which carries the chemical to organs throughout the body, including the brain (Herkenham et al., 1990). There, THC connects to cannabinoid receptors on nerve cells and influences the activity of those cells (Herkenham et al., 1990). Some brain areas have many cannabinoid receptors, while others have few or none. Many cannabinoid receptors are found in the parts of the brain that influence pleasure, memory, thought, concentration, sensory and time perception, and coordinated movement (Herkenham et al., 1990).

When marijuana is smoked, its effects begin immediately after the drug enters the brain, lasting between one and three hours (Herkenham et al., 1990). If marijuana is consumed in food or drink, the short-term effects begin more slowly, usually in less than one hour, but may last for as long as four hours. Smoking marijuana deposits several times more THC into the blood than does eating or drinking the drug (Herkenham et al., 1990).

Within minutes of inhaling marijuana, an individual's heart begins to beat more rapidly, the bronchial passages relax and become enlarged, and blood vessels in the eyes expand, making the eyes look red. The heart rate, normally 70 to 80 beats per minute, may increase by 20 to 50 beats per minute or, in some cases, even double (Gilman et al., 1998). This effect can be greater if other drugs are taken contemporaneously with marijuana (Foltin et al., 1987). As THC enters the brain, it causes a user to feel euphoric by acting in the brain's reward system--areas of the brain that respond to stimuli (e.g., food and drink). THC activates the reward system in the same way that nearly all drugs of abuse do, by stimulating brain cells to release the chemical dopamine (French, 1997).

A marijuana user may experience pleasant sensations, colors and sounds may seem more intense, and time appears to pass very slowly. The user's mouth feels dry, and s/he may suddenly become very hungry and thirsty. A user's hands may tremble and grow cold. The euphoria passes after a period of time, and then the user may feel sleepy or depressed. Occasionally, marijuana use produces anxiety, fear, distrust, or panic.

Heavy marijuana use impairs a person's ability to form memories, recall events, and shift attention from one thing to another (Pope and Yurgelun-Todd, 1996). THC also disrupts coordination and balance by binding to receptors in the cerebellum and basal ganglia, the parts of the brain that regulate balance, posture, coordination of movement, and reaction time (Pope and Yurgelun-Todd, 1996). Through its effects on the brain and body, marijuana intoxication can lead to automobile accidents. Studies have shown that approximately 6-11 percent of fatal accident victims test positive for THC (Cimbura et al., 1990). Marijuana users who have taken high doses of the drug may experience acute toxic psychosis, which includes hallucinations, delusions, and depersonalization--loss of the sense of personal identity, or self-recognition (Graham et al., 1998). Although the specific causes of these symptoms remain unknown, they appear to occur more frequently when a high dose of cannabis is consumed in food or drink rather than smoked (Graham et al., 1998).

Social Effects of Marijuana Use

Students who smoke marijuana get lower grades and are less likely to graduate from high school, compared with their non-smoking peers (Lynskey and Hall, 2000; Kandel and Davies, 1996). Workers who smoke marijuana are more likely than their coworkers to have problems on the job. Several studies have associated workers' marijuana smoking with increased absences, tardiness, accidents, workers' compensation claims, and job turnover. A study among postal workers found that employees who tested positive for marijuana on a pre-employment urine drug test had 55 percent more industrial accidents, 85 percent more injuries, and a 75 percent increase in absenteeism compared with those who tested negative for marijuana use (Zwerling et al., 1990).

Depression, anxiety, and personality disturbances (Brook et al., 2001, 1998) are all associated with marijuana use. Research has demonstrated that marijuana use can cause problems in daily life or exacerbate a person's existing problems. Because marijuana compromises the ability to learn and remember information, the more a person uses marijuana the more s/he will have difficulty accumulating intellectual, job, or social skills (Block and Ghoneim, 1993).

Research has also shown that marijuana's adverse impact on memory and learning can last for weeks after the acute effects of the drug subside (Block and Ghoneim, 1993). A study of 129 college students found that among heavy marijuana users, defined as those who smoked the drug at least 27 of the preceding 30 days, skills related to attention, memory, and learning were significantly impaired, even after they had not used the drug for at least 24 hours (Pope and Yurgelun-Todd, 1996). Heavy marijuana users had more trouble sustaining and shifting their attention and in registering, organizing, and using information than did the study participants who had used marijuana no more than three of the previous 30 days (Pope and Yurgelun-Todd, 1996).

Another study confirmed that marijuana's effects on the brain can cause cumulative long-term deterioration of critical life skills. Researchers gave students a battery of tests measuring problem-solving and emotional skills to students in 8th grade and then again in 12th grade (Scheier and Botvin, 1996). The results showed that the students who were already drinking alcohol and smoking marijuana in 8th grade lagged behind their peers, but that the distance separating the two groups grew significantly by their senior year in high school. The analysis linked marijuana use, independently of alcohol use, to reduced capacity for self-reinforcement, a group of psychological skills that enable individuals to maintain confidence and persevere in the pursuit of goals (Scheier and Botbin, 1996).

Marijuana users have poor outcomes on a variety of measures of life satisfaction and achievement. A recent study compared current and former long-term heavy users of marijuana with a control group who reported non-heavy lifetime marijuana use. Despite similar education and incomes in their families of origin, significant differences were found on educational attainment and income between heavy users and the control group (Gruber et al., 2003). When asked how marijuana affected their cognitive abilities, career achievements, social lives, and physical and mental health, an overwhelming majority of heavy cannabis users reported the drug's deleterious effect on all of these measures (Gruber et al., 2003).

Addiction Potential

Long-term marijuana use can lead to addiction. According to the 2005 National Survey on Drug Use and Health (NSDUH), approximately 23.2 million persons aged 12 or older (9.5 percent of the population) needed treatment for an illicit drug or alcohol use problem (SAMHSA, 2006). In 2005, the specific illicit drug that had the highest levels of past year dependence or abuse was marijuana (4.1 million) (SAMHSA, 2006). Along with cravings, withdrawal symptoms can make it difficult for long-term marijuana smokers to stop using the drug (Budney et al., 2003).

MARIJUANA IN THE UNITED STATES

The United States policy towards marijuana is best viewed two-dimensionally: 1) supply reduction, or the reduction and control of the supply of drugs through legal prohibitions, law enforcement, interdiction, sentencing, and incarceration; and 2) demand reduction, or the reduction of the demand for drugs through education, prevention, and treatment (MacCoun and Reuter, 1997). The history of each reduction policy is reviewed below.

Supply reduction

On August 2, 1937, Congress passed the Marijuana Tax Act, (1) which was signed into law on August 2, 1937. The Act placed marijuana into the same category as cocaine and opium- it became illegal to import marijuana into the United States (Inciardi, 2003). As predicted by the American Medical Association and others who fought the passage of the bill, it did not curb marijuana use. By the early 1940s, narcotic addiction had all but disappeared in the United States. This was not the result of a medical breakthrough or the result of legislative initiatives. Rather, the Second World War interrupted the opium trafficking routes from Europe. In October 1970, President Nixon signed into law the Comprehensive Drug Abuse and Prevention and Control Act. (2) Known as the Controlled Substances Act of 1970, it consolidated more than 50 drug laws into one that was designed to control the legitimate drug industry and to curtail importation and distribution of illicit drugs.

One aspect of the Controlled Substances Act was the schedule of drugs. Schedule I articulates those substances which have no accepted medical utility, but have substantial potential for abuse, including heroin, marijuana, and various hallucinogens. Schedule II lists substances having a high abuse liability, but also having some accepted medical purpose, such as morphine and cocaine. The Act did, with respect to criminal penalty, select out marijuana from other drugs and lowered the maximum penalty for possession of an ounce of marijuana to one year in jail and a $5,000 fine, with the option of probation or a conditional discharge at the judge's discretion (Slaughter, 1988).

The 1980s saw the passage of four major anti-drug bills, all within the supply reduction arena. First, the Comprehensive Crime Control Act of 1984 (3) broadened criminal and civil asset forfeiture laws and increased federal criminal sanctions for drug offenses. Second, the 1986 Anti-Drug Abuse Act, (4) while providing money for prevention and treatment, also restored mandatory prison sentences for large-scale distribution of marijuana and imposed new sanctions on money laundering. Third, the 1988 Anti-Drug Abuse Amendment Act (5) increased the sanctions for crimes related to drug trafficking and set in place new federal offenses. Sentences were determined by the quantity of the drug involved, "conspiracies" and "attempts" were punished as severely as completed acts, and possession of a hundred marijuana plants carried the same sentence as possession of a hundred grams of heroin. Fourth, the Crime Control Act of 1990 (6) was aimed at supply reduction and law enforcement, doubling the appropriations for drug law enforcement grants to states and localities and strengthening forfeiture and seizure statutes.

Demand reduction

Federal legislation in the demand reduction area (prevention and treatment) is sparse compared to that of supply reduction. The first piece of federal legislation that was demand reduction oriented was the Porter Narcotic Farm Act of 1929, which provided for the U.S. Public Health Service to establish federal hospitals specifically for the treatment of imprisoned addicts. In 1962, the Supreme Court in Robinson v. California (7) held that addiction to narcotics was, in and of itself, an illness and not a criminal offense. This led to an increase in federal treatment efforts. The Community Mental Health Centers Act of 1963 (8) established specialized addict treatment grants, bringing narcotic addiction into the realm of mental illness and enabling federal support for local drug treatment efforts.

In 1966, Congress passed the Narcotic Addict Rehabilitation Act. (9) The legislation called for addicts charged with federal crimes to be civilly committed rather than face prosecution, and it allowed the court to mandate a treatment program in lieu of prison. It also permitted the establishment of a treatment program for addicts not charged with other crimes. In all cases, before civil commitment could occur, the addict had to be judged by the court as likely to be rehabilitated.

Federal efforts in demand reduction activities probably did not begin as a major or focal activity until the passage of the Drug Abuse Office and Treatment Act of 1972. (10) This law created the Special Action Office for Drug Abuse Prevention to establish objectives for all federal demand reduction programs. The National Institute on Drug Abuse was created to be the center piece for a major federal effort in demand reduction. In spite of this serious effort at centralization, federal efforts within the demand reduction arena remained highly fragmented. Federal legislation in the demand reduction area from that time until the present has taken on the task of trying to centralize and provide leadership to drug abuse demand reduction activities. Legislation established the Alcohol, Drug Abuse and Mental Health Administration (ADAMHA) in 1974, and other legislation established SAMHSA as the successor to ADAMHA.

With respect to marijuana demand reduction activities, the closest effort came in the creation of the National Commission on Marijuana and Drug Abuse in 1970. The Commission's role was to examine the nature and extent of drug abuse demand reduction activities and issue annual reports on findings, conclusions, and suggest needed future activities. In its 1972 report, the Commission recommended that decriminalization of marijuana be considered. The Nixon Administration rejected this proposal. While marijuana was certainly included in many demand reduction activities of the federal effort, it has never been explicitly legislated.

The history of cannabis legislation is not the same as the social or public policy it reflects. During the Nixon and Ford years, public policy towards all drugs including marijuana was highly restrictive. While there was acknowledgement of demand reduction, the major emphasis was clearly on supply reduction and enforcement. With the Carter years (1977-1980) came a very clear distinction between narcotics and marijuana. The federal position under the Carter Administration was that a move towards decriminalization was a state-by-state choice and should not be mandated by the federal government.

The Reagan-Bush years (1981-1992) heralded an increasing emphasis on law enforcement, seizures, and interdictions. While high level policy groups at the White House level were coordinating both supply and demand reduction strategies, the emphasis of the strategies were markedly supply oriented. The current policy emphasized during the Reagan-Bush years was "zero tolerance." Within the Clinton and Bush Administrations (1992-present), drug abuse on both the supply and demand sides was low profile. It must be noted, however, that provisions of mandatory sentencing, forfeiture, and seizure, as set forth in the Reagan-Bush years, are still in place and actively enforced.

State policy

There is wide variation in both the nature and extent of anti-marijuana laws found in each state. All are subject to the federal legislation discussed above, but tremendous variation exists not only between states but, in many cases, by counties and jurisdictions within states. While several states have decriminalized possession of small amounts of marijuana, most states have either not changed their marijuana laws or have taken an even stronger pro-enforcement stance. For example, possession of less than one ounce of marijuana in New York brings a $100 fine. That same amount of marijuana found in Nevada constitutes a felony. Even as a first offense, selling a pound of marijuana in Montana could draw a life sentence. The nature and extent of state marijuana laws is thus wide and varied.

Prevalence of Marijuana Use

Data on the prevalence of illicit drug use in the United States, the world's largest single market for illicit drugs, (11) come from three major data collection efforts, each of which provides information on a specific population. The NSDUH (12) generates self-report survey estimates of drug use among household members ages 12 and older (SAMHSA, 2006). Since the 1970s, Monitoring the Future (MTF) has surveyed more than 50,000 grade school, high school, and college students annually on their drug-using beliefs, attitudes, and behaviors (Johnston et al., 2007). The Arrestee Drug Abuse Monitoring (ADAM) Program collected self-report drug use data and urine specimens from adult and juvenile arrestees nationwide between 1987 and 2003 (Yacoubian, 2004). The ADAM Program was the only surveillance system in the United States to collect both self-report and objective (urine specimens) drug use measures (Yacoubian, 2004).

In 2005, an estimated 19.7 million Americans aged 12 or older, or approximately eight percent of the population, were current (past 30-day) illicit drug users (SAMHSA, 2006). Marijuana is the most prevalent illicit drug within the American household population, with 14.6 million persons 12 or older reporting its use during the past 30 days (SAMHSA, 2006). Of these persons, about one-third used it at least 20 of those 30 days (SAMHSA, 2006). In 2006, the most prevalent current illicit drug among high school seniors, 10th graders, and 8th graders was marijuana. Nearly half (48%) of all seniors reported lifetime marijuana use, while approximately 36% reported marijuana during the past year and 21% in the 30-day period preceding the interview (Johnston et al., 2007). Among 10th graders, lifetime marijuana use was reported by 25% of the sample, while lifetime marijuana use among 8th graders use was 12% (Johnston et al., 2007).

In 2000, 64 percent or more of adult male arrestees, in more than half of the 35 ADAM sites, tested positive by urinalysis for at least one of five drugs: cocaine, marijuana, opiates, methamphetamine, or PCP (National Institute of Justice (NIJ), 2001). As measured by urinalysis, cocaine and marijuana were the two most prevalent illicit drugs (NIJ, 2001). Marijuana is the drug used most commonly by adult male arrestees. Urinalysis revealed that an average of 40 percent of arrestees had used marijuana recently (NIJ, 2001). Use was lowest in Laredo (30 percent) and highest in Oklahoma City (57 percent) (NIJ, 2001). Among younger (18-20 year-old) arrestees, urinalysis showed marijuana-positive rates starting at 49 percent (Portland) and rising to 81 percent (Albuquerque) (NIJ, 2001). Heavy marijuana use is defined as 13 or more days of self-reported use in a 30-day period in the year before the interview. In half the sites, 29 percent or more of younger adult male arrestees used marijuana heavily (NIJ, 2001). The highest self-reported rates of heavy marijuana use among younger arrestees were in New York City (57 percent), Sacramento (48 percent), Indianapolis (39 percent), and Birmingham and Philadelphia (both 38 percent) (NIJ, 2001).

These drug surveillance systems are the primary tools used by the United States government to develop national drug control policy. Taken collectively, they provide a comprehensive snapshot of drug use in the United States. While natural fluctuations have occurred during the past three decades, only one reasonable conclusion can be drawn from the body of prevalence data we have at our disposal--that significant marijuana use pervades all sectors of American society despite the punitive marijuana control policy approach taken by the United States government.

MARIJUANA IN THE NETHERLANDS

Soon after the founding of the Dutch East Indies Company, Holland had a thriving business trading in cocaine and opiates (French, 2005; Haag and Taekema, 2004; Tak, 2002; Leuw and Haen Marshall, 1994). It has been estimated that nearly 10 percent of the income earned by the Dutch colonies between 1816 and 1915 stemmed from the opium trade (Haag and Taekema, 2004; Tak, 2002; Leuw and Haen Marshall, 1994). In response to international pressures, however, the Netherlands enacted the Opium Act in 1919, banning the opium trade. Cannabis trade was formally banned in 1953 (Haag and Taekema, 2004; Tak, 2002; Leuw and Haen Marshall, 1994).

While Dutch drug policy is more tolerant than any other Western nation, their drug control policy is complex and often misunderstood. Dutch law states without ambiguity that marijuana is illegal. That said, in 1976 the Netherlands adopted a formal policy of nonenforcement for violations involving the possession or sale of up to 30 grams (lowered to five grams in 1995) of marijuana. This policy is referred to depenalization (MacCoun and Reuter, 1997)

By the mid-1980s, small retail outlets (coffee shops) were permitted to sell marijuana legally (MacCoun and Reuter, 1997). This policy is referred to as de facto legalization (MacCoun and Reuter, 1997). The coffee shops are required to comply with five regulations: 1) sales are limited to no more than five grams per person daily; 2) no hard drugs, such as ecstasy, cocaine, or heroin, can be sold; 3) no advertising is permitted; 4) no nuisances or public disturbances are permitted; and 5) no sales to minors (Horstink-Von Meyenfeldt, 1996; Ministry of Foreign Affairs et al., 1995). Most of the coffee shops offer an international variety of marijuana with varying levels of potency (MacCoun and Reuter, 1997). A typical establishment offers between five and 25 varieties, along with non-alcoholic beverages and baked goods (MacCoun and Reuter, 1997).

The key question emanating from the Netherlands marijuana policies is whether depenalization and de facto legalization have led to increased marijuana use. The available evidence suggests that, among adolescents, marijuana use stayed fairly constant in the Netherlands between 1976 and the mid-1980s (MacCoun and Reuter, 1997). While depenalization had virtually no effect on levels of marijuana use, sharp increases of marijuana use were witnessed between 1984 and 1996 when retail access to marijuana increased. For persons between the ages of 18 and 20, for example, 30-day marijuana use increased from 8.5 percent to 18.5 percent (MacCoun and Reuter, 1997). As a comparison, data from the United States and Norway, two countries that aggressively enforce marijuana bans, indicated that during this same time frame use among youth declined (MacCoun and Reuter, 1997). These findings are consistent with the hypothesis that relaxed enforcement of marijuana laws leads to increases in marijuana consumption.

More recent, longitudinal data (1997 and 2001) from the National Prevalence Surveys (NPO) on marijuana use in the Netherlands demonstrate increases in marijuana use within the general population (Netherlands Institute of Mental Health and Addiction (NIMHA), 2006). In 2001, 17 percent of respondents 12 years of age or older reported lifetime marijuana use, as compared to 15.6 percent in 1997 (NIMHA, 2006). Only three percent of respondents in 2001 reported 30-day marijuana use, as compared to 2.5% in 1997 (NIMHA, 2006). Not surprisingly, marijuana use was most prevalent among respondents between the ages of 16 and 19 and between 20 and 24. Among 16-19 year-olds, 30-day marijuana use increased from eight percent in 1997 to 8.6 percent in 2001, while increasing among 20-24 year-olds from slightly more than seven percent in 1997 to 11.2 percent in 2001 (NIMHA, 2006).

In addition, the NPO collect data on location of marijuana procurement. In 2001, respondents between the ages of 12 and 17 obtained marijuana primarily from friends and acquaintances (46 percent) and in coffee shops (37 percent), while respondents 18 years old and older procured their marijuana primarily from coffee shops (47 percent) and friends and acquaintances (36 percent) (NIMHA, 2006). The findings for marijuana procurement among 12-17 year-olds are curious given that coffee shops are not permitted to sell marijuana to clients under the age of 18.

Since the early 1980s, the Dutch National School Survey (DNSS) has been conducted to estimate the prevalence of illicit drug use among students aged 12 and older at secondary schools throughout the Netherlands. The data demonstrated a strong increase of current marijuana use between 1988 and 1996 among both male and female students, but between 1996 and 2003 rates decreased sharply for male students (NIMHA, 2006). Rates of current marijuana use remained constant for the female students between 1996 and 2003 (NIMHA, 2006). According to the DNSS, students who used marijuana exhibited more aggressive and delinquent behavior and had more school-related problems (e.g., truancy and poor grades) than their non-using counterparts (Monshouwer et al., 2005). Among DNSS respondents, approximately two-third obtained their marijuana from friends, while more than one-third procured their marijuana from coffee shops (Monshouwer et al., 2005)

The DNSS also collected marijuana use data from "special" youthful populations, including bar-goers, students participating in truancy projects, marginalized youth, club attendees, school dropouts, detainees, and coffee shop attendees. Of these special populations, current marijuana use ranged from a low of 14 percent (students in special schools) to a high of 88 percent (coffee shop frequenters) (NIMHA, 2006). Approximately one-quarter of bar-goers and 40 percent of club attendees reported current marijuana use (NIMHA, 2006). Approximately 60 percent of juvenile detainees reported marijuana use in the 30 days preceding detention (NIMHA, 2006).

DISCUSSION

This essay sought to investigate three primary questions. First, what are the major distinctions between the United States and the Netherlands with respect to drug policy? Second, is there empirical evidence to indicate that the United States and/or the Netherlands have succeeded in reducing marijuana use? Third, should the law of the United States be changed to reflect the more relaxed system in the Netherlands, taking into consideration politics, empirical evidence, and cultural norms?

The primary difference between the United States and the Netherlands with respect to marijuana control policy is philosophical. In the United States, drug control policy generally and marijuana control policy specifically have followed an identical path--prohibition. The United States has enacted strict drug control laws, operating under the assumption that drug offenses require severe sanctions because of the harm they inflict upon the individual and society (a non-utilitarian approach to punishment) and that repeat and potential drug users will be deterred by these draconian sanctions and abstain from engaging in the behavior (implicating the utilitarian approaches of specific and general deterrence). This general prohibitionist philosophy has translated into [primarily] a supply-oriented control policy--reducing the amount of drugs entering the United States and imposing severe sanctions for drug law violations.

In contrast, the Netherlands approach to marijuana control is more liberal. The Netherlands still officially criminalize marijuana, but have, for nearly 30 years, implemented two policies that effectively relax the enforcement of their marijuana laws. The first--depenalization--is a formal policy of nonenforcement for violations involving the possession or sale of up to five grams of marijuana. The second policy--de facto legalization--permits the sale of marijuana, with several regulations, by coffee shops throughout the Netherlands.

Social scientists and policymakers should be guided by empirical evidence when evaluating a particular policy. In the case of the Netherlands, the evidence, though antiquated and sparse, seems to suggest that while depenalization had little effect on subsequent rates of marijuana use, de facto legalization (i.e., proliferation of coffee shops) led to sharp increases of marijuana use among Dutch youth. This finding is consistent with a body of alcohol, tobacco, and other illicit drug (ATOD) use prevention research that has focused on environmental strategies for reducing the prevalence and associated harms of illicit drugs (Yacoubian, 2007; Birckmayer et al, 1994; Holder, 1998). Simply put, as physical availability of ATOD increases, so does use. Thus, it would be unreasonable to even hypothesize that increased availability could lead to decreased use.

In contrast, the enactment and enforcement of strict marijuana laws should, in theory, reduce the use of marijuana. The available evidence in the United States, considerably more robust than the data from the Netherlands, suggests that marijuana use rates have remained constant, within a variety of populations, for the several decades. While natural fluctuations have occurred, it seems clear that the United States' policy toward reducing marijuana use has not been particularly successful.

A comparison between these two divergent marijuana control policies leads to the ultimate debate of whether one is superior to the other. Based purely on available empirical evidence, the answer is unknown. It is difficult to assess the efficacy of a Dutch policy that has not been reliably evaluated. Moreover, the United States' policy is not particularly encouraging--billions of dollars are spent annually on supply side efforts that do not appear to have significantly reduced marijuana consumption.

Clearly, more data are needed to make an informed decision. Such a research endeavor, however, is difficult to conceptualize and is likely fraught with methodological problems. First, any study in the Netherlands today that would attempt to evaluate the impact of coffee shops would require asking survey 'respondents to report future drug-using behaviors if the availability of marijuana through retail outlets was suddenly reduced or eliminated. It is hard to imagine a scenario where reduced availability would lead to increased use--full criminalization of marijuana could not possible have the effect of sustaining current users and encouraging new use. Second, marijuana use is not the only outcome vanable of interest. Harms and problems associated with the re-criminalization of marijuana use in the Netherlands would be affected. At the very least, marijuana-related crime and operating costs of the Dutch criminal justice system would necessarily increase.

Without more information, the classic criminalization versus decriminalization debate prevails (Yacoubian, 2001; MacCoun and Reuter, 1997). Ultimately, states are likely going to be guided by their obligations under international treaty law and political realities. Countries like the United States, who for decades have taken a conservative stance on drug issues, will likely not sway from that path. States like the Netherlands, whose liberal attitudes toward social problems have led to more relaxed marijuana laws, may be faced with outside pressures to conform to the prevailing view. When the issue is illicit drug use and the harms associated with it, more conservative policies tend to be more appealing, even without empirical support.

Correspondence concerning this article should be addressed to: Dr. George S. Yacoubian, Jr., Office of the District Attorney, 3 South Penn Square, Philadelphia, PA, 19107-3499, or by email to [e-mail].

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(1) Pub. L. 238 (Aug. 2, 1937).

(2) 21 U.S.C. 13 (1970).

(3) Pub. L. No. 98-473 (1984).

(4) Pub. L. No. 570 (1986).

(5) Pub. L. No. 100-690 (1988).

(6) Pub. L. 101-647 (1990).

(7) 370 U.S. 660 (1962).

(8) 42 U.S.C.A. [section] 2671 (1968).

(9) Pub. L. 89-793 (1966).

(10) Pub. L. 92-255 (1972).

(11) Id.

(12) Formerly the National Household Survey on Drug Abuse.

George S. Yacoubian, Jr., J.D., Ph.D.

Prosecutor, Office of the District Attorney

Philadelphia, PA & a Senior Associate with ICF International, Fairfax, VA