Common Sense Theory
In the end, researchers found that 28 boys a quarter of the total number who used both illegal and legal drugs at some point during the study followed the reverse gateway sequence, meaning they started out smoking pot and then moved on to alcohol or tobacco. Additionally, they found that the reverse gateway population was no more likely to develop a substance abuse problem than those who progressed through the gateway, from alcohol to pot.
The researchers also sought to identify the characteristics that distinguished each group that is, they wanted to find out if there was anything that distinguished the boys who ended up going down the traditional gateway path from those who reversed that course. In the end, they found three differentiating variables, according to a Pitt press release: Reverse gateway users were more likely to have grown up in neighborhoods with a "poor physical environment," were more likely to be exposed to drug use in the neighborhood, and were less likely to have parents who were involved in their lives.
The study groundbreaking in scope and scale is significant for several reasons, chief among them is that the work suggests that environmental factors have more influence on behavior than the government would like to admit. Indeed, when White House Office of National Drug Control Policy czarina Bertha Madras rolled into Austin in October, she took great pains to explain to the Chronicle that recent research involving adolescent rodents given pot at a very young age and then, later, given an opportunity to self-administer heroin proved that the gateway theory was valid, precisely because it removed all outside factors and concentrated exclusively on the physical properties of addiction. (That study was far less significant than she made it out to be, in part because, in the end, the two groups of rats one group had been exposed to pot, the other hadn't were equally likely to become addicted.) Here, though, in a study of humans, living in real life situations, researchers found that "environmental aspects have stronger influence on which type of substance is used," Pitt reported. In other words, it isn't the drug itself that is, pot that leads to substance abuse, no über-powerful villainous weed descending from above and casting innocents down into a life of debauchery; rather, it's a combination of factors chief among them, significantly, the environment in which the use begins.
Researchers say these are the hallmarks of an "emerging" theory they call the "common liability model," which posits that "the use of illegal drugs is determined not by the preceding use of a particular drug, but instead by the user's individual tendencies and environmental circumstances." This is a theory otherwise known as common sense.