Schaffer Library of Drug Policy

Marihuana: A Signal of Misunderstanding

Marihuana and (Non-Violent) Crime - Crimes Under the Influence

US National Commission on Marihuana and Drug Abuse

Table of Contents
I. Marihuana and the Problem of Marihuana
Origins of the Marihuana Problem
The Need for Perspective
Formulating Marihuana Policy
The Report
II. Marihuana Use and Its Effects
The Marihuana User
Profiles of Users
Becoming a Marihuana User
Becoming a Multidrug User
Effects of Marihuana on the User
Effects Related to Pattern Use
Immediate Drug Effects
ShortTerm Effects
Long Term Effects
Very Long Term Effects
III. Social Impact of Marihuana Use
IV. Social Response to Marihuana Use
V. Marihuana and Social Policy
Drugs in a Free Society
A Social Control Policy for Marihuana
Implementing the Discouragement Policy
A Final Comment
Ancillary Recommendations
Legal and Law Enforcement Recommendations
Medical Recommendations
Other Recommendations
Letter of Transmittal
Members and Staff
History of Marihuana Use: Medical and Intoxicant
II. Biological Effects of Marihuana
Botanical and Chemical Considerations
Factors Influencing Psychopharmacological Effect
Acute Effects of Marihuana (Delta 9 THC)
Effects of Short-Term or Subacute Use
Effects of Long-Term Cannabis Use
Investigations of Very Heavy Very Long-Term Cannabis Users
III. Marihuana and Public Safety
Marihuana and Crime
Marihuana and Driving
Marihuana - Public Health and Welfare
Assessment of Perceived Risks
Preventive Public Health Concerns
Marihuana and the Dominant Social Order
The World of Youth
Why Society Feels Threatened
The Changing Social Scene
Problems in Assessing the Effects of Marihuana
Marihuana and Violence
Marihuana and (Non-Violent) Crime
Summary and Conclusions: Marihuana and Crime
Marihuana and Driving
History of Marihuana Legislation
History of Alcohol Prohibition
History of Tobacco Regulation
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The Report of the National Commission on Marihuana and Drug Abuse

Marihuana and (Non-Violent) Crime


The Philadelphia survey on marijuana use and crime asked several questions concerning 16 different offenses. The questions began as follows: "'Many people in every community commit acts which others consider offenses, delinquent acts, and violations. Here is a list of these acts." The specific questions dealt with whether the respondent had ever committed each one, how often, how old lie was when the offense occurred, whether lie was caught by the police, and whether the respondent had been drinking, or was under the influence of marijuana, 24 hours or less before committing the act-as well as whether the respondent thought that using marijuana influenced him to commit the act; these questions were asked about the first as well as the most recent such of. fense, if they occurred. The offenses were: hurting someone in a minor way, hurting someone badly, carrying a knife. stealing a car, disturbing people, threatening to hurt someone, taking money, stealing from a store, making an obscene telephone call, forcing sexual intercourse with a woman, breaking into a house or store, damaging property, buying stolen property, setting off an alarm, carrying a gun, and using a weapon to steal. From these facts, it might be interesting to find out what proportion of acts involved some drug use occurring within 24 hours-and whether that drug is alcohol or marijuana. I will explain after the data are presented what these facts can and cannot tell us. We must not be too hasty in reading too much into any given set of data.

Table 2 presents summary information from this set of questions. I have presented figures for only six offenses: stealing from a store, damaging property, hurting someone in a minor way, breaking into a house or store, stealing a ear, and hurting someone badly. Some of the crimes asked about were committed by so few respondents (such as forcing sexual intercourse) that any statistical analysis would be completely meaningless. Other offenses seem to be unrelated to the aggressive syndrome associated with marijuana use-such as buying stolen property. The six I have chosen are, in any case, representative. Tile first three are relatively minor, and would usually be classified by the law as misdemeanors; the second two are considerably more serious, and would often be classified as felonies. Table 2 presents the proportion who drank alcohol, and smoked marijuana 24 hours or fewer before the crime was committed; the figures in the first two columns are for the first time the respondent committed the offense, and the second two columns are for the most recent time, if it occurred more than once.

What generalizations may we make front Table 2?

First of all, committing these crimes is atypical. Not one these six offenses was committed by a majority of the sample. Secondly the more serious the offense, the less likely it was to be committed. Minor offenses were committed at least once by between four and five out of every 10 respondents, but major offenses had been committed at least once by something like one respondent in 25. (And two of the offenses not in the table were rarer still; forcing sexual intercourse was admitted to by six respondents, or about one in 100, and using a weapon to steal was reported by only three respondents, or one out of 200.)

What about drugs and crime? Compared with not being under the influence, drugs tend to be atypical in the commission of crimes. For none of these categories, whether first offense or most recent, was being under the influence of either alcohol or marijuana characteristic of over a quarter of all offenses, and most are considerably below this. Most crimes here were committed when the offender was not under the influence of any drug, marijuana, or alcohol, when lie was in a "normal" state of mind pharmacologically.* Secondly, in terms of absolute incidence, alcohol is involved in the commission of crime considerably more often than marijuana. Adding together all of the offenses committed 24 hours before each drug was used, alcohol had been used in conjunction with first offenses a total of 47 times, and marijuana only five times-a ratio of not quite ten to one. For the most recent offenses, alcohol was involved a total of 66 times, and marihuana 19--a ratio of about three to one.

In conjunction with this point, it should be stressed that the classic, aggressive, violent crimes traditionally and historically associated with the marijuana intoxication are very, very rarely committed-by anyone, high or normal, user or non-user alike. Six men in this survey admitted to forcing a woman to have intercourse with him as a first offense, and three admitted to rape more than the first time. In two out of the six first-time cases, the offender said that he had been drinking 24 hours before, and in one out of the three most recent-time cases, drinking was involved as well. But in none of the six first time cases, and in none of the three recent-time cases, had anyone smoked marijuana 24 hours before. (None of the men had been apprehended for this offense, incidentally.) Only three of the men in the survey said that they had used a weapon to steal as a first offense, and two admitted this offense more than the one time-and none said that lie had either drunk or smoked 24 hours before the offense.

*Several facts should he born in mind when considering this generalization. First of all, the survey asked about the use of each drug 24 hours before the offense was committed or less-and hence, the respondent was not necessarily under the influence when the offense was committed, although certainly many respondents were under the influence at that time. Secondly, anyone who uses marijuana is far more likely to become intoxicated with each episode of use than is true of each episode of alcohol use.

Considering the fact that the typical marijuana smoker in this study had been intoxicated several hundred times for a total of well over a thousand hours, and therefore in a state of mind which, if the "causal" theory is correct, is aggressive and criminogenic, then this almost total absence of violent and aggressive crimes committed by users should be puzzling. This fact indicates that the "causal" theory may be inadequate and erroneous.

However, it is not possible to tell from Table 2 whether the commission of crimes is more frequent for alcohol or marijuana on a relative basis during the period of intoxication. That is, if anyone wanted to know whether a thousand hours of a marijuana or an alcohol intoxication was more like to result in the commission of various crimes, this table would not convey this information. Unfortunately, this survey did not ask a question on the frequency with which the respondents drank alcohol or, indeed, whether they drank at all so that an alcohol -marijuana comparison cannot be more systematically made. It is entirely possible that alcohol-related crimes are far more frequent than marijuana-related crimes. simply because alcohol is still, even in this sample, probably the drug of choice among young people, and is more often used than marijuana (just as not being under tile influence of any drug is more frequently involved with crimes than being under the influence, simply because most people, most of the time, are not intoxicated). As to which drug is more "criminogenic" in the sense of what proportion of the time under the influence of marijuana vs. alcohol one commits various crimes cannot be determined from the data from this study. However, in absolute terms, alcohol is considerably more often used before crimes than marijuana.

Another generalization that may be made from Table 2 is that the contribution of marijuana from first offense to most recent offense grows somewhat relative to alcohol. That is, for the first offense, alcohol is used before it about 10 times as frequently as is marijuana, but for most recent offense, alcohol is only three times as frequent. This probably is a reflection of the following two trends: (1) Marijuana smoking is considerably more frequent today (i.e., closest in time when the most recent offense occurred) titan a few years ago (i.e., closest in time when the first offense occurred), and hence, its frequency relative to alcohol would be greater in conjunction with any activity-criminal or non-criminal as well-simply because its use is more common ; (2) Marijuana smoking is more common among young adults (the age group most closely represented by the age when last offense was committed) than among adolescents and preadolescents (the age group most closely represented by the age when first offense was committed) and, moreover, as age rises, marijuana use rises faster than alcohol use rises, at least up, until early adulthood. . . .

It is possible that, as marijuana usage increases, the number of crimes committed under the influence of this drug may increase as well. However, the question as to marijuana's direct contribution to the commission of crimes, especially aggressive crimes, is ail independent issue, and one in need of exploration.

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