Between mid-1980s and the end of the century, the number of arrests for drug offences rose considerably in the countries of the European Union. It was twofold in Denmark and Italy, for example, and sixfold in Belgium, Greece, Spain, Portugal and Finland. Cannabis was the drug most often involved in arrests. Depending on the country, drug offenders accounted for between 15% and 50% of the total jail population in the EU, while drug use was reported in the case of 30% to 90% of prisoners.
2. A lot of drug-related offences are committed by people who would not otherwise be involved in crime. Property crime, such as robbery, is fairly rational, carried out by those who see it as their only way to generate income to finance their drug habit. Such people are now certainly more prepared to carry weapons with them -- particularly knives. They will do anything, ranging from stealing from their mothers to committing violent robberies, because the addictive effect of class A drugs, such as heroin, are so strong.