There is a Dutch saying “gelegenheid maakt de dief” which means that occasion creates the thief. This proverb is essentially the behind the theory on crime prevention developed by Dutch criminologist Jan van Dijk.
According to professor Van Dijk too much emphasis is put on the perpetrator’s side and too less on the victim’s one. (No, he is not blaming the victim, as we will see.) Here is a diagram of Van Dijk’s theory on the development of crime rates.
After world war two the economy of West-Europe and North America experienced a rapid growth and more people enjoyed economic prosperity. As a result people own more stuff and hence there is more occasion for theft. So crime rates are rising.
Rising crime rates result in more fear for crime and, this is the important point, will cause people to protect themselves. Home owners will invest in better locks, businesses will hire private security. And due to increased protection the occasion for (property) crime decreases and hence crime rates fall.
This model is on contrast to many popular explanations for falling crime rates in the western worlds such as decreased poverty, changed demographics (i.e. aging) and legalized abortion. These popular explanations are, according to Van Dijk, problematic and lack empirical evidence.
The importance of this theory is that according to professor Van Dijk, the government can take effective measures to prevent crimes. He gives several real world examples.
First he mentioned a 1960 German law which mandates steering wheel locks in German cars. Due to this law there were less thefts in cars than in other West European countries. Similarly a West Australian law requiring engine immobilizers caused to sharp decline in this type of crime compared to the rest of Australia.
Secondly professor Van Dijk points out that in countries such as England and the Netherlands, where the law requires certain security measures in homes there are fewer burglaries than in countries such as Denmark and Switzerland where such legislation is lacking.
The important lesson is that physical security or situational prevention works and that this is far more effective than more police or heavier punishments.
For those who understand Dutch, here is a video where professor van Dijk explains his model: