"Cannabis continues to be the illicit drug most often mentioned in reported drug law offences in Europe (34). In the majority of European countries, offences involving cannabis accounted for between 50% and 90% of reported drug law offences in 2010. Offences related to other drugs exceeded those related to cannabis in only four countries: the Czech Republic and Latvia with methamphetamine (54% and 34%); and Lithuania and Malta with heroin (34% and 30%).
"In the period 2005–10, the number of drug law offences involving cannabis increased in 15 reporting countries, resulting in an estimated increase of 20% in the European Union. Downward trends are reported by Germany, Italy, Malta, the Netherlands and Austria (35)."

Source

European Monitoring Centre for Drugs and Drug Addiction, "Annual report 2012: the state of the drugs problem in Europe" (Luxembourg: Publications Office of the European Union, November 2012), Catalog No. TDAC12001ENC, doi:10.2810/64775, p. 36.
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