"The information we have presented adds to the current literature on the impacts of decriminalization. It disconfirms the hypothesis that decriminalization necessarily leads to increases in the most harmful forms of drug use. While small increases in drug use were reported by Portuguese adults, the regional context of this trend suggests that they were not produced solely by the 2001 decriminalization. We would argue that they are less important than the major reductions seen in opiate-related deaths and infections, as well as reductions in young people’s drug use. The Portuguese evidence suggests that combining the removal of criminal penalties with the use of alternative therapeutic responses to dependent drug users offers several advantages. It can reduce the burden of drug law enforcement on the criminal justice system, while also reducing problematic drug use."
Hughes, Caitlin Elizabeth and Stevens, Alex, "What can we learn from the Portugese decriminalization of drugs?" British Journal of Criminology (London, United Kingdom: Centre for Crime and Justice Studies, November 2010), Vol. 50, Issue 6.