Marijuana and the ‘Gateway Theory’


Experts agree that the use of marijuana is not causally linked to the use of other illicit substances

  • “This study is the first to use nationally representative data across all 50 states and the District of Columbia to comprehensively explore the broader impacts of RMLs [recreational marijuana laws], providing some of the first evidence on how marijuana legalization is affecting illicit drug use, heavy alcohol use, arrests for drug and non-drug offenses, and objectively-measured adverse drug-related events including drug-related overdose deaths and admissions into substance abuse treatment services. … [W]e find little compelling evidence to suggest that RMLs result in increases in illicit drug use, arrests for part I offenses, drug-involved overdoses, or drug-related treatment admissions for addiction.”
  • “Marijuana use has been proposed to serve as a ‘gateway’ that increases the likelihood that users will engage in subsequent use of harder and more harmful substances, known as the marijuana gateway hypothesis (MGH). The current study refines and extends the literature on the MGH by testing the hypothesis using rigorous quasi-experimental, propensity score-matching methodology in a nationally representative sample. … Results from this study indicate that marijuana use is not a reliable gateway cause of illicit drug use. As such, prohibition policies are unlikely to reduce illicit drug use.”

Sequentially, most consumers of illicit substances first experimented with either alcohol or tobacco

Statistically, the overwhelming majority of people to try marijuana do not go on to use other illicit drugs, and most typically cease their use of marijuana by middle age

In jurisdictions where marijuana is legally accessible, adults typically report decreasing their use of other controlled substances. In this sense, marijuana appears to act more as a potential ‘exit drug’ rather than as an alleged ‘gateway’

In clinical settings, marijuana use is associated with reduced cravings for cocaine and opiates