"As in previous years, the measure aimed at providing a solution to the drug problem which scored highest is the education provided at schools (backed by 91.8% of the population). The second most highly-supported measure is voluntary drug user treatment (84.9%), followed by police and Customs supervision (84.2%) (Table 2.51 and Fig. 2.50).
"On the contrary, the measures which are considered to be least effective are those regarding legalization. The legalization of all drugs shows a 20.9% support, meaning a 5.3 percentage point rise compared to 2009, although still far from the level encountered ten years ago (27.1%). Support of the legalization of cannabis has been growing since 2007, up to 32.7% of the population found to support cannabis legalization in the last measurement taken. Similarly, the degree of support is not as high as ten years ago (38.5%).
"Similarly, other measures considered to be effective by more than 80% of the citizens are the publicity campaigns (81.0%) and the strict anti-drug laws (80.3%). Hence, the measures considered most highly effective by citizens are the informative measures, voluntary treatment, police control and legal restriction."

Source

Government Delegation of National Plan on Drugs (Reitox National Focal Point for Spain), "2012 National Report (2011 Data) to the EMCDDA: Spain: New Development, Trends and in-depth information on selected issues" (Madrid, Spain: DGPNSD, Dec. 2012), p. 105.
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