Criminal laws prohibiting marijuana possession do not deter marijuana use

A California police officer's study concluded, "The reduction in penalties for possession of marijuana for personal use does not appear to [be] a factor in people's decision to use or not use the drug."
REFERENCE: California State Office of Narcotics and Drug Abuse. 1977. A First Report on the Impact of California's New Marijuana Law. State Capitol: Sacramento.

Criminal laws prohibiting marijuana possession do not deter marijuana use

In surveys, most individuals cite health concerns and family responsibilities rather than legal concerns as their primary reasons for ceasing (or never initiating) marijuana use.
REFERENCE: National Academy of Sciences, Institute of Medicine (IOM). 1982. Marijuana and Health. National Academy Press: Washington, DC.

Criminal laws prohibiting marijuana possession do not deter marijuana use

Marijuana laws have no "specific" deterrent impact on drug taking behavior. Studies show that marijuana offenders continue to use marijuana after their conviction at rates equal to those prior to their arrest. No relation between the actual or perceived severity of their previous sentence and subsequent use has been found.
REFERENCE: P. Erickson. 1980. Cannabis Criminals: The Social Effects of Punishment on Drug Users. Addiction Research Foundation: Toronto.

Criminal laws prohibiting marijuana possession do not deter marijuana use

Marijuana users believe that their behavior will go undetected; thus fear of arrest is usually not a factor in people's decisions whether or not to use it.
REFERENCE: Canadian Centre on Substance Abuse National Working Group on Addictions. 1998. Cannabis Control in Canada: Options Regarding Possession. Ottawa.

Criminal laws prohibiting marijuana possession do not deter marijuana use

Marijuana use remains consistent despite a high level of enforcement, and there is no detectable relationship between changes in enforcement and levels of marijuana use over time.
REFERENCE: J. Morgan and L. Zimmer. 1997. Marijuana Myths, Marijuana Facts: A Review of the Scientific Evidence. The Lindesmith Center: New York, 46.