"The most important act with regard to drug law offences is the Opium Act, which defines the trafficking, production, cultivation, dealing and possession of illegal drugs as criminal acts, when these activities take place outside of the conditions mentioned in the Opium Act Decision and the Regulation Opium Act Exemptions. The drugs in question are named in schedule I (‘hard drugs’ like heroin, cocaine, amphetamines or ecstasy) and schedule II (‘soft drugs’ like cannabis or hallucinogenic mushrooms) of the Opium Act. The possession of drugs is a criminal act and therefore theoretically the use of drugs may be a criminal act as well. This reasoning was part of a verdict of the Council of State (Raad van State 201009884/I/H3 2011). The Prosecutor, however will never prosecute consumption of drugs per se.
"Preparative activities for the illegal production, sale or export of hard drugs are also criminal acts according to the Opium Act (article 10a). These imply also possession of substances which are meant to be used for the illegal production of hard drugs (see for instance LJN: BW8614 2012).
"The Prevention of Abuse of Chemicals Act is also of importance for the combat of drug-related crime, especially with regard to precursors of synthetic drugs. In addition, administrative law plays an increasing role in the combat of drug-related crime on the local and regional level."

Source

Van Laar, M.W., Cruts, A.A.N., Van Ooyen-Houben, M.M.J., Van Gageldonk, A., Croes, E.A., Meijer, R.F., et al. (2013). The Netherlands drug situation 2012: report to the EMCDDA by the Reitox National Focal Point. Trimbos-instituut/WODC, Utrecht/Den Haag, p. 118.
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