Section 3 criticized the assertion that marijuana use is related to risk perception. The research cited to support the assertion did no more than provide an affirmation of the consequent of the assertion. A rival hypothesis was presented, which was that if non-use of marijuana was related to risk perception, than use of marijuana would be correlated with the absence of risk perception. An examination of the National Household Survey data suggests that many individuals who do not believe marijuana is risky still do not choose to use the drug. This suggests that health concerns may not have as much influence in drug use as policy makers believe, or as argued in section 3 that many adults simply don't believe the government when it comes to claims about marijuana and health.

There are arguments for both positions. Lloyd Johnston is the project director for the Monitoring the Future Project. In a 1988 paper, Johnston and his colleagues try to explain the decline in school-age marijuana use during the 1980's by testing two theories, 1) lifestyle variables, such as being more conservative, explain the drop, and 2) that risk perception explains the drop in use. They found that lifestyle variables did not explain the drop, but that changing attitudes about marijuana and health did.(4)

"the perceptions of greater risks "got the ball rolling" and provided the basis for increased personal disapproval and decreased (perceived) use by friends and acquaintances with each succeeding class of seniors since 1979.

". . . Early efforts to dissuade students from use of marijuana often made exaggerated claims about harmful effects; meanwhile students could observe readily that friends and acquaintances who used marijuana did not suffer such disastrous consequences. More recently, however, reports about the health consequences have been more balanced, have received better and more extensive media coverage, and have been based on much more extensive research. Similarly, reports about psychological consequences, such as poor school performance, reduced interest in extracurricular activities, and impaired interpersonal relationships have now acquired the ring of truth: regular use of marijuana (and other drugs) has been widespread for a long enough time to give most students first-hand contact with at least a few classmates who fit the popular description of "burnout". Indeed, we have found that daily marijuana users themselves perceive some such consequences as stemming from their use of the drug. Thus it seems that direct observation, and the resulting vicarious learning, have become consonant in recent years with messages from "the system.""(5)

In 1990 the authors published another study testing the same hypothesis with cocaine use, and they reached the same conclusion that use reduction is correlated with risk perception.(6) If one accepts this assertion, then what is one to make of the recent series of increases in adolescent marijuana use during the early 1990's? Does this mean that the government warnings have not held up to scrutiny, or does it mean that risk perception just isn't as important a factor as first believed?

The exaggerated claims about the danger presented by potent marijuana were discussed in section 4. These claims were an integral part of the anti-marijuana warnings of the mid-1980's Johnston and colleagues praise in the excerpt above. Furthermore, these mid-1980's health warnings were based on "new evidence" of the period which has since been discredited by the recognition that marijuana's effects are receptor-based, not membrane-based as once believed. This is particularly relevant to the proposition that marijuana use leads to "burnout" in some teenage users, a symptom of the amotivation syndrome supposedly created by a desensitization in brain cells. This phenomenon has since been shown not to exist. Since these once-praised findings have since been shown to be faulty, is it a surprise that marijuana use has begun to increase?