During 1971 and 1972 I was a consultant for the National Commission on Marihuana and Drug Abuse, which was mandated in 1970, under the provisions of the Comprehensive Drug Abuse Prevention and Control Act, to conduct an extensive study on the effects of marijuana. I was asked by the commission to conduct research and write monographs on two fundamental marijuana issueswhether marijuana use "caused" violent and criminal behavior, and whether it "led to" the use of more dangerous drugs, notably heroin. A number of other studies were conducted by other researchers. I would like to summarize the findings and conclusions from my monograph on the use of marijuana and dangerous drugs, which was itself a summary of dozens of surveys and studies on this issue. Since the original monograph was almost volume-length, I will present only its conclusions.
Of the many surveys on the use of marijuana and other drugs, probably all have demonstrated an empirical association. The marijuana user has a statistically higher likelihood of trying and using a wide range of dangerous drugs than is true of the nonuser; frequency of marijuana use is similarly associated with dangerous drug use. The basic problem, however, is not the existence of this relationship but just what it means in a causal sense. There are many statistical associations that are in no way causally related. For instance, one observer has pointed out that the drinking of tomato juice is statistically correlated with becoming intoxicated (Kupperstein 1971). Clearly, tomato juice has no intoxicating properties whatsoever; the fact that it is often mixed with vodka in "Bloody Marys" produces an accidental or spurious association between the ingestion of tomato juice and intoxication. Another study found that coffee drinkers are more likely to use dangerous drugs than individuals who do not drink coffee (Blum et al. 1969, pp. 57-58). Does this indicate a causal relationship between the ingestion of coffee and using drugs? Many studies have shown a correlation between liberal politics and ideology and using marijuana. Does using marijuana "cause" someone to adopt liberal politics? Certainly agreeing with these propositions would be fallacious. An amusing book of two decades ago, entitled How to Lie with Statistics (Huff 1954), discussed dozens of such methodological and factual blunders in reasoning. We must be careful not to make similar errors in exploring the marijuana-dangerous drug link. It would be erroneous to automatically translate the statistical correlation into a causal process. Thus we want to know whether the relationship between marijuana and dangerous drugs is spurious that is, an incidental feature of some other relationshipor whether marijuana use actually causes the use of other, more dangerous drugs.
There are a number of different and to some degree contradictory explanations of the cause behind this statistical association. The first is the biochemical, or "effects," theory, which claims that it is the experience of the marijuana intoxication itself that provides the dynamic force in drug "escalation" This biochemical explanation has several variants. One is that being high on marijuana provides an introduction to the drug experience, thus stimulating a "thirst" for bigger and better "thrills." A former director of the Bureau of Narcotics and Dangerous Drugs has written: "The evidence is strong that the use of marihuana develops a taste for drug intoxication which, in turn, leads many people to the use of more potent drugseven heroin" (Giordano 1968, p. 5).
A variant of the biochemical theory is the tolerance disillusionment explanation. According to this line of reasoning, initial experimentation with marijuana leads to ever greater involvement with the drug; this in turn leads to diminishing effects. Eventually, the marijuana user finds the experience of becoming intoxicated on the drug unexciting, banal, and less pleasurable; hence he turns to more potent drugs to achieve the high he initially felt, but can no longer achieve, with marijuana. A proponent of this view is the Attorney General of the United States, John Mitchell, who was quoted as saying that marijuana... can be a dangerous and damaging drug.... l think we'll find physical and chemical evidence of that.... If we have a national commission to undertake a study and report its findings, then we have... more information and evidence that will be acceptable to the public. For example,... a commission could make clear the distinction between addiction and dependency. A kid gets into steady use of marijuana. After a while he gets less of a charge from it, and this psychological dependency causes him to move on to the harder stuff. ... We have got to get proof that it does create this dependency [my emphasis] (Newsweek, September 7,1970, p. 22).
The basic metaphor indicated by these two variations of the biochemical explanation is that of a conveyor belt. Heroin addiction is seen as a later stage of a process that begins with marijuana use. If marijuana use is halted, slowed down, or diminished, fewer drug users will be produced at the other end. John Ingersoll, the present director of the Bureau of Narcotics and Dangerous Drugs, has been quoted as saying:... it is a matter of record that the explosion in marijuana use has been accompanied by a sharp upturn in heroin use.... We know that the overwhelming majority of those who use heroin or LSD... have had prior experience with either marijuana or hashish. Thus it seems reasonable to assume that if many individuals did not get involved with marijuana, they would never get around to using the more potent dangerous drug [my emphasis] (U.S. News and World Report, May 25, 1 970).
The view that a certain number of marijuana users translates into a certain proportion of heroin addicts was the guiding principle underlying the government's "Operation Intercept" and "Operation Cooperation." It also dominates the theory that the decriminalization and ready availability of marijuana would eventually and inevitably produce a greater number of heroin addictsbecause more people would be smoking marijuana, which leads to heroin use.
Another theory explaining the statistical relationship between marijuana use and the use of dangerous drugs, especially heroin, is the personality abnormality approach. According to this view, it is only, or mainly, the psychiatrically inadequate who "escalate" from marijuana to dangerous drugs. Among those with sound and healthy personalities, marijuana does not necessarily or typically produce this progression. To put it another way, the greater the ego inadequacy of the individual, the greater the likelihood of drug escalation. Experimenting with marijuana may be the sign of a minor, or even possibly of no, psychiatric problem. Becoming seriously involved with marijuana may be the sign of a severe problem. And experimenting with and becoming involved with the heavy use of drugs such as heroin, methedrine, and LSD is almost certainly a sign of something seriously wrong with the user's psyche. Individuals with a severe problem will not find in marijuana a sufficient "solution" to their problem. They will therefore "shop around" for some drug that will answer or mask their psychiatric difficulties. Thus, this theory holds, both marijuana use (to a minor degree) and the use of dangerous drugs (to a major degree) are external manifestations of an internal turmoil. One implication of this theory is that marijuana use per se has relatively little to do with the escalation process. In fact, marijuana use is a kind of "dead end" search: those with serious psychiatric problems will discard that particular solution and look about for another one. In this sense, then, rather than "leading to" the use of more dangerous drugs, marijuana use may actually retard the process.
The third theory or explanation for the progression from marijuana to dangerous drugs is the social, or subcultural, model. This view holds that marijuana use per se has little or nothing to do with why some users "go on" to the use of more dangerous drugs. The answer lies almost entirely within the kinds of social relationships and friendships that users establish in the course of taking drugs. Drug use inevitably entails making and sustaining social interactions and human relationships in conjunction with using drugsit is not simply the ingestion of a chemical substance. Making drug-related friendships involves making friendships of a particular type. This will influence one's further behaviorparticularly in relation to drug use. These social relationships are variable, not constant. Within certain social and cultural milieus, the marijuana-to-heroin escalation may existbecause of the nature of the groups using these drugs and because of social patterns arbitrarily related to drug use. But in different groups this escalation may be totally lacking, because the friendships or relationships established do not have anything to do with the use of dangerous drugs. It does not depend on the biochemical effects of the drugs themselves, but on the characteristics of the groups using drugs, the norms and values and beliefs held within subcultures. The escalation process (where and when it does occur) does not come about as a result of anything intrinsic to the drug itself or to the experience of being high; rather it relates to the nature of the personal associations one makes in the course of using drugs.
What evidence do we have to support or refute these various theories and explanations?
Although personality and psychiatric factors may play a role in drug escalation, it is clear from available systematic studies that (I) the biochemical theory of the progression from marijuana to dangerous drugs is completely false and invalid, and (2) the sociocultural theory explains more of the variation in drug escalation, if and when it does occur, than any other model currently proposed.
The disenchantment process proposed by the proponents of the biochemical theory does not even remotely occur; in fact, precisely the opposite takes placethe more that an individual smokes marijuana, the more that he feels and enjoys its effects. Rather than a desensitization, what actually occurs is an increased sensitization. From the results of dozens of studies on the subjective effects of marijuana among experienced, long-term users, a few of which were described in Chapter 2, it is clear that under the influence of the drug users experience, and continue to experience, effects such as euphoria, relaxation, heightened sexual feeling, greater sensitivity, increased pleasure in listening to music, and so on. When users are compared with respect to frequency of use, exactly the opposite occurs as would be predicted by the disillusionment theory; it is not the occasional user who describes the most frequent and most pleasurable effects, but rather the heavy, frequent, chronic user. (Of course, a dialectical relationship is taking place here; those who enjoy the experience tend to repeat it.) In one study only 23 percent of the occasional users reported always feeling an "increased sexual pleasure" while high; this was true of 39 percent of the chronic users. Of the occasional users 35 percent reported always feeling an "intensified sense of taste," but 49 percent of the chronic users said this (Hochman and Brill 1971).
My own study verified this basic finding. Effects such as paranoia, depersonalization, and depression become less commonly reported the more that the individual used marijuana. Pleasurable effects become increasingly prominent. For instance, when I divided my sample into three use levelsthree times a week or more, once or twice a week, and less than once a week52 percent of the frequent marijuana users said that the drug stimulated their sexual desires, but less than 30 percent of the infrequent users agreed. Similarly, of those who had had sex while under the influence of marijuana, 77 percent of the frequent users claimed that marijuana increased their sexual enjoyment, and only 49 percent of the infrequent users agreed (Goode 1970, pp. 162-167).
What the data on the relationship between degree of involvement with marijuana and subjective effects show is that heavy, chronic, extended use does not conform to the classic tolerance-disillusionment model proposed by the adherents of the biochemical hypothesis. If a drug progression does occur, it is quite decidedly not because of tolerance, of a reduction in chemical or psychological responsiveness to the drug. It is specifically the chronic user who tends to enjoy marijuana's effects the most, and it is also the chronic user who is most likely to experiment with other drugs. It is therefore necessary to abandon the tolerance explanation for drug escalation, if and when it does occur.
The other biochemical modelthe "bigger kicks, greater thrills" theoryis inadequate simply because it does not specify any variables. It is known that not all marijuana users "go on" to the use of heroin or other dangerous drugs; in fact, only a very small proportion do so. Thus we are still left with the question of why some (a minority) do and others (the majority) do not. The view that marijuana itself develops in the user a "thirst" to try bigger and better things is invalidated by the fact that all marijuana users go through the same experiencegetting highyet there is enormous variability in whether or not they "go on" to the use of more dangerous drugs. A constant condition cannot explain a variable outcome. Consequently, again, we have to seek an explanation elsewhere.
In my own study of multiple-drug use (Goode 1969), I found a remarkable "concatenance of many factors relating to marijuana use." The study showed that a given user's likelihood of experimenting with more dangerous drugs was closely related to his involvement with and in a drug-using subculture. The greater the proportion of marijuana-using friends an individual had (which was itself highly correlated with frequency of smoking marijuana)and the more that an individual was "insulated" from nonusing friendsthe more likely he was to use other, more dangerous drugs. About 64 percent of the respondents in my study who had 60 percent or more marijuana-using friends had themselves tried LSD; but only 26 percent of the respondents who had less than 30 percent marijuana-using friends had tried LSD themselves. Thus marijuana use can be seen as a kind of index of one's involvement with a drug-using subculture, with a community of fellow drug users. The more that one uses marijuana, (1) the more favorable will be the views of one's friends toward using drugs other than, and in addition to, marijuana (most users of illegal dangerous drugs continue to use marijuanaheroin addicts are a major exception); (2) the greater the likelihood that one will become involved in selling marijuana; (3) the more one will learn about the workings of the underground drug market; (4) the further one will become involved with the drug-using community; and (5) the greater will be one's opportunities for trying and using other dangerous drugs. Thus it is not the biochemical properties of marijuana itself that "lead to" the use of dangerous drugs; rather it is the social and cultural milieus in which marijuana useand especially frequent marijuana usetakes place.
This analysis was taken a step further by sociologist Bruce Johnson, whose work has been cited earlier in this volume. In 1970 Johnson distributed questionnaires to 3,500 college students in and around the New York metropolitan area. His findings demonstrated the crucial role of the marijuana user's place in the drug subculture as a determinant of dangerous drug use. Johnson divided his sample into four levels of marijuana useabstainers, experimental users (less than monthly), moderate users (monthly or more but less than weekly), and regular users (weekly or more). The outcome, or dependent variable, that which is to be explained, was the use of heroin (although fundamentally the same relationship was found with the use of other dangerous drugs). Johnson found, as I did, and as do all researchers investigating this phenomenon, a positive, linear, and significant statistical association between marijuana use and the use of dangerous drugs. Less than I percent of the marijuana abstainers in Johnson's survey had tried heroin. This was true of 1 percent of the experimental users, 5 percent of the moderate users, and 17 percent of the regular users. The same relationship held for the use of the other dangerous drugshallucinogens, amphetamines, barbiturates, methedrine, and cocaine. Johnson concluded that "the more frequent the use of marijuana, the greater the likelihood of using any and all other dangerous drugs" (Johnson 1972).
Johnson then set out to determine what variables influenced the relationship between frequency of marijuana smoking and the use of dangerous drugs. A crucial explanatory variable in Johnson's study was differential exposure to dangerous drug-using friends. By holding marijuana use constant, Johnson was able to test the relative strength of frequency of marijuana use and having heroin-using friends as determinants of heroin use. He found that almost none of the marijuana abstainers in his survey had tried heroin, whether or not they had heroin-using friends. But among experimental marijuana smokers, 5 percent of those with at least one heroin-using friend had tried heroin themselves; this was true of only.5 percent of those marijuana experimenters with no heroin-using friends. Among regular marijuana users, only 5 percent of those without heroin-using friends had tried heroin themselves, but 45 percent of the regular users with at least one heroin-using friend had tried heroin. As one moved from experimental to regular use of marijuana, the concomitant use of heroin rose only slightly, when heroin-using friends is controlled. But as one moved from not having to having heroin-using friends, the likelihood of using heroin rose markedly. It is obvious that having heroin-using friends is far more potent in influencing heroin experimentation than is the level of marijuana use. Even the regular use of marijuana does not "lead to" the use of heroin in the absence of having heroin-using friends.
What variables, then, influence making friends with those who use heroin? One researcher has suggested that buying and selling drugs play an independent role in determining involvement in the drug subculture (Carey 1968). Johnson tested this lead and found that involvement in the buying and selling of illegal drugsparticularly drugs other than marijuanawas the single most potent variable determining whether or not one had heroin-using friends. Among the respondents in his survey who had only bought (but not sold) marijuana (and no other drugs), 4 percent of the experimental marijuana users and 8 percent of the regular users had at least one heroin-using frienda very small increase. Among those who had both bought and sold marijuana as well as other drugs, 25 percent of the experimental users of marijuana and 36 percent of the regular users had at least one intimate heroin-using friend. This relationship can be looked at in two ways. The jumps from 4 to 8 percent and from 25 to 36 percent (that is, the impact of degree of marijuana use on having heroin-using friends) are fairly small. But the jumps from 4 to 25 percent and from 8 to 36 percent are quite significant. Thus it is clear that involvement in selling drugs is considerably more potent and influential in having heroin-using friends, and hence using heroin, than is the factor of frequency of use of marijuana. The original correlation between frequency of use and the use of dangerous drugs is largely due to involvement in selling drugs, not to use itself. Buying but not selling only marijuana did not influence the relationship very much at all, but selling, and especially selling drugs other than marijuana, did influence the relationship powerfully. Thus the causal link between marijuana use and the use of dangerous drugs does not appear to be the use of marijuana at all. Use of marijuana is merely an external manifestation of something that underlies itnamely, involvement with and in a drug-using subculture, especially in the form of buying and selling illegal drugs, and having friends who use other dangerous drugs.
These data do not answer the question of whether or not a psychiatric abnormality plays a role in the escalation process. But if it alone is determinative, then quite clearly the independent role of marijuana is inconsequential. If heroin experimentation and addiction (as well as the use of other dangerous drugs) answer a deep psychic need for oblivion, degradation, escape, or whatever, marijuana is merely a fairly easily available drug that presents itself at a relatively early age and is eventually discarded as a "solution" to the problems of the user. Thus marijuana is actually a "digression," to adopt one observer's phrase (Joyce 1971); it serves to slow down the progress to heroin rather than to facilitate it (Kaplan 1970). If anything, the personality abnormality model discounts marijuana's independent role in the escalation process.
Thus two factors account for the greater use of dangerous drugs among marijuana users in comparison with nonusers: (1) a process of selective recruitment, and (2) a process of selective interaction and socialization. The selective recruitment process largely explains why young alcohol drinkers and cigarette smokers are more likely to "go on" to the use of marijuana and dangerous drugs. This same process determines why marijuana users are more likely to engage in liberal politics and to be more permissive sexually. It also underlies the apparently anomalous correlation, noted earlier, between coffee drinking and illegal drug use. The explanation is simply that almost no social group or category, almost no set of participants in any activity, forms a random selection of a total society. There will be a wide range of differences in participants versus nonparticipants in any activitynot because the activity necessarily has anything to do with the differences observed but because some other factor or variable is meaningfully associated with the two together, producing an apparent, or spurious, relationship between them. Knowing this fundamental fact will insulate us from making absurd causal inferences. This does not mean that no relationships are meaningfulonly that we have to search carefully to see whether they are in fact significant, systematic, and causal.
There is a relationship between the use of any and all drugs and the use of any and all other drugs, whether they are legal or illegal. This relationship was verified by the Narcotic Addiction Control Commission's study of 7,500 randomly selected residents of New York State (Chambers 1971). Regular users of barbiturates (four-fifths of whom obtained all their supply legally, via prescription) were ten times as likely to use amphetamines, heroin, methedrine, and LSD than was the general population. Does using barbiturates legally "lead to" the use of heroin? Users of diet pills were five times as likely to be regular users of heroin, and twelve times as likely to use LSD and methedrine, than was true of the general population. Does taking diet pills "lead to" the use of illegal dangerous drugs? The point is that there is to some extent a drug-taking orientation or "disposition," just as there is an abstention orientation. Even before someone tries a drug, legal or illegal, for the first time, he is already different from a peer who will never use drugs. Individuals who use drugs tend to be selectively recruited from segments of the population that are oriented toward the use of drugs. Illegal nonmedical drug use is correlated even with frequency of taking aspirin (Estes and Johnson 1971), not because there is any direct causal link between the two but because there are some points of similarity in social characteristics between the kinds of people who use drugs and the kinds of people who take aspirin. Marijuana use is not spread evenly across the population. It is necessary to pay attention to the social characteristics and personality make-up of marijuana smokers to remind ourselves that many relationships between marijuana use and almost anything else could be accounted for solely by the fact that marijuana users are simply differentwith or without marijuana use. We have to hold these differences constant before making any inferences as to the "effects" of the drug, or its "causal" impact.
The second processthat of selective social interaction and socializationalso operates with marijuana use. Not only are marijuana users different even before they smoke their first marijuana cigarette, they also become different by the distinctive social relations they engage in during the course of their marijuana-related activities. I have emphasized two such activities and interactions that have special relevance for the escalation process: buying and selling drugs, and making friendships with others who use dangerous drugs. (There are, of course, other indicators of one's involvement with the drug-using subculture.) The crucial difference between marijuana "leading to" the use of more dangerous drugs and legal drugs "leading to" the use of dangerous drugs is that there is a definite subculture of marijuana usersand even more so of users of such drugs as methedrine, LSD, and heroin whereas the term "subculture" cannot be meaningfully applied to those who use legal drugs such as alcohol and sedatives. The strong parallels between the use of legal drugs and illegal drugs can be carried only so far. The subterranean status of marijuana makes its use more than simply a question of selective recruitment into a specific activity by a certain "deviant" segment of society. The very criminal status of marijuana gives its use, possession, and sale an added socialization and subcultural power not evidenced by the possession and use of the legal drugs. One of the reasons that marijuana users are to some degree insulated from conventional society is the fact that the drug is illegal. And it is this very insulation that gives the drug-using subculture its socializing power, and that provides some of the force behind the progression from marijuana to more dangerous drugs.
The data I have presented point very strongly to the conclusion that the "conveyor belt" metaphor of drug escalation is invalid. If marijuana possession were decriminalized and placed under legal controls similar to those for alcohol, the drug would eventually lose its subterranean character. This would give the marijuana subculture less "specialness" and less socializing power. And the link with the use of other dangerous drugs would be attenuated. The correlation would not, of course, disappearit still exists with the legal drugs. But the marijuana-dangerous drug correlation would become no different from that between the current legal and illegal drugs. As John Kaplan has pointed out, it is legitimate to ask "whether or not the criminalization of marijuana is part of the problem, rather than the solution" (Kaplan 1970, p. 260). In the case of the escalation process, this appears to be quite clearly true. Far from producing more addicts, as the "conveyor belt" metaphor indicates, it is likely that legalization would produce fewer, by taking the young marijuana user out of a criminal drug-using subculture. (This is not to be regarded as a "solution" to the heroin problem as well; there are other, massive causes for heroin addiction, and the decriminalization of marijuana would not make much of a difference.) The specific patterns that the escalation process follows show the invalidity of retaining marijuana's criminal status. Our legal policies in regard to marijuana have been a gigantic mistake. It is time to correct that error.
1. I do not discuss the monograph on marijuana use and criminal behavior because the issue is less likely to be taken seriously today than is the question of whether marijuana leads to dangerous drugs.(back)
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