John Morgan and Lynn Zimmer

John Morgan and Lynn Zimmer maintain in the following viewpoint that no causal link has been established between the use of marijuana and the use of harder drugs. In fact, the vast majority of marijuana users never go on to use hard drugs. Morgan is a professor of pharmacology at the City University of New York Medical School. Zimmer is a sociologist at Queens College in New York. Both serve as directors for the National Organization for the Reform of Marijuana Laws, an organization that works for the legalization of marijuana, and coauthored the 1997 book Marijuana Myths, Marijuana Facts: A Review of the Scientific Evidence.

As you read, consider the following questions:

1. According to the authors, why is the statistic that marijuana users are 85 times more likely than non-marijuana users...