Professor Alex Stevens:

As far as I know, there is no place in the world that has legalised all drugs, unless the Senator considers the medical market to be a full legalisation. For example, there is a legal market for heroin. It is done by prescription. Normally, the legalisation that has taken place has focused on cannabis. There has been some legalisation of psilocybin in magic mushrooms, for example, in the Netherlands and Australia.

If we focus on cannabis, a wide range of options are in use internationally. The Germans have just legalised the possession, production and sale of cannabis, but only in specific circumstances. For example, it is okay for private citizens to cultivate a small number of plants and even to share their allowance by adopting what is known as the cannabis social club model. That has also occurred in Belgium and Spain, where people have used the fact that they are allowed to grow a certain number of plants to pool their allowance and share it between them and that becomes a kind of self-producing co-operative model. That is one extreme of the most tightly controlled model.

People can do that in Uruguay but there is also a system in Uruguay of licensed sellers and licensed buyers. In Uruguay, people who have a licence to do so can buy cannabis legally, if they are doing so from a business that has a licence to produce. That is a rather contrasting and more limited model than the one in some of the states in America. For example, in California there is a much more free market model, where we have seen a great diversification of cannabis products, some of which have extremely high potencies. There is also a rather peculiar situation in America where because cannabis is illegal at a federal level, there is no way to control advertising, so quite a lot of open promotion and advertising of cannabis can be seen.

In the evidence on what are known as temptation goods, which include such things as tobacco and alcohol, there is a fairly clear link between advertising, marketing and price promotion and increased use. There are models of the legalisation of cannabis that we would expect to increase use, because that is what we have seen with other temptation goods when there is a free market. However, it is not necessary to legalise using a free market approach. It is possible to have a much more restrictive means of enabling people to get a legal supply of cannabis without being punished either for production or possession.