A common public opinion is that marijuana is often used as a stepping stone drug, progressively leading to the use of harder, class A drugs such as heroin and cocaine.
While statistics have shown that the use of cannabis in individuals aged 17 or under correlates to them being up to five times more likely to use harder drugs in the future, scientists have extensively proven that there is nothing in the substance that leads to other drugs. (Lynskey 2003)
Instead it is the social aspect of using marijuana and other drugs that must be considered in relation to the stepping stone or gateway theory. It is the contact with sellers of illegal drugs which puts marijuana users at a higher risk of being exposed to and urged to use harder drugs, not the drug itself.
According to Morral (2002) the people who are predispositioned to use drugs and have the opportunity to use drugs are more likely than others to use marijuana and other drugs. Marijuana typically comes first because it is more available. A very simple analogy that can help display this is the comparison between bicycle riders and motorcycle riders. As explained by Zimmer (1997) most people who ride a motorcycle (a fairly rare activity) have ridden a bicycle (a fairly common activity). Indeed, the prevalence of motorcycle riding among people who have never ridden a bicycle is probably extremely low. However, bicycle riding does not cause motorcycle riding, and increases in the former will not lead automatically to increases in the latter.
It is also worth considering that for most drug users, marijuana is not the first drug they have taken. It is alcohol and tobacco that should be considered as the initial step of the theory, as if there is to be such a