The Commission's review of the available evidence bearing on the relationship between marihuana use and criminal, aggressive and delinquent behavior has yielded the following information.

The once prevalent belief among the general public and the professional law enforcement, criminal justice and research communities that marihuana causes crime, violence, aggression and delinquency has moderated appreciably over the years. Recent evidence indicates that increased attention has been devoted, instead, to a possible statistical correlation rather than a cause-effect relationship.

At present, however, considerable confusion and uncertainty exists among both the general and professional publics, among youth and adults, and among marihuana users and non-users about the relationship between marihuana and criminal, aggressive or delinquent behavior. The confusion and uncertainty stem from a general lack of knowledge and understanding about the effects of the drug, including its potential for physical addiction. Many persons are still under the misapprehension that marihuana is addicting and that crimes are committed in order to support a drug "habit."

In general, recent changes in public and professional opinion have corresponded with and reflected the increased use of marihuana, particularly within the middle class segment of society; more direct observation of and professional experience with the marihuana user; new and more enlightened information about the drug and its effects; and concomitant changes in the public image of the user.

There is no systematic empirical evidence, at least that drawn from the American experience, to support the thesis that the use of marihuana either inevitably or generally causes, leads to or precipitates criminal, violent, aggressive or delinquent behavior of a sexual or nonsexual nature.

Laboratory studies of effects have revealed no evidence to show that marihuana's chemical properties are, by themselves, capable of producing effects which can be interpreted as criminogenic; that is, that marihuana is an independent cause of criminal or aggressive behavior. If anything, the effects observed suggest that marihuana may be more likely to neutralize criminal behavior and to militate against the commission of aggressive acts.

The research community has recently gathered considerable evidence to show that marihuana and criminal, aggressive and delinquent behavior are statistically and significantly correlated when measured together in isolation from variables which are related to marihuana use and other forms of antisocial behavior. The data also show, however, that this statistical association either attenuates significantly or disappears completely when the proper statistical controls are applied.

In other words, the observed relationship between the, use of marihuana and criminal, violent, aggressive and delinquent behavior is spurious. It is dependent on such extra-pharmacological factors as the age, race and education of the user; the type of community in which he lives; his past history of psychosocial maladjustment; and his involvement in a criminal or delinquent subculture (use of other drugs; drug buying and selling activities; associations with friends who also use, buy and sell cannabis or other drugs).

To reiterate what Professor Goode has so cogently stated,

If there were truly a causal relationship between marihuana use and crime, these disappearing correlations would not occur. The application of sociological variables cannot wash out a chemical reaction in the user (1972:52).

To put it still another way, to believe that marihuana causes criminal, violent, aggressive or delinquent behavior is to confuse the effects of the drug with the people who use it.

From the perspective of marihuana's relationship to antisocial behavior of a criminal or violent nature, the drug cannot be said to constitute a significant threat to the public safety. If its use, therefore, is to be discouraged, it must be discouraged on grounds other than its role in the commission of criminal or violent or delinquent acts.

The enormous increases in marihuana arrests over the past several years are ample evidence that the police have taken seriously their role of maintaining law and order with respect to marihuana use and that they have responded to public pressure and concern about the increase in marihuana use. Yet, in their experience with the marihuana user they have been placed in the unenviable position of having to enforce a law either disregarded or discredited by large segments of the population they serve.

Over and over again they have seen their efforts in this respect negated by the de jure or de facto modification, if not nullification, of the laws against possession by prosecutors, judges and even legislators. Their increasing frustration and demoralization, therefore, at least with respect to the marihuana user, is quite, understandable.

These other officials, however, are likewise placed in a difficult position; for they, too, must enforce and apply the criminal law, and they, too, must respond to public pressures and concerns. In some instances, they have demonstrated particular resistance to criminalizing the user and subjecting him to criminal penalties which are deemed to be unwarranted if not unwise.

In the case of marihuana, recent changes in law enforcement practices with respect to the user have, in fact, reflected the increased use and public tolerance of marihuana. The statutory changes now taking place at the state and local levels are further evidence of the trend toward greater public acceptance of the user. In these instances, the laws and their enforcement were altered because they no longer performed the symbolic function of expressing society's disapproval of marihuana use.