Andrew Sullivan recently reported on some interesting research into the consequences of state-level marijuana legalization.
A 2012 research paper by the Mexican Competitiveness Institute in Mexico called ‘If Our Neighbours Legalise’, said that the legalisation of marijuana in Colorado, Washington and California would depress cartel profits by as much as 30 per cent. A 2010 Rand Corp study of what would happen if just California legalised suggests a more modest fall-out. Using consumption in the US as the most useful measure, its authors posit that marijuana accounts for perhaps 25 per cent of the cartels’ revenues. The cartels would survive losing that, but still. “That’s enough to hurt, enough to cause massive unemployment in the illicit drugs sector,” says [fellow at the Mexico Institute at the Wilson Center David] Shirk. Less money for cartels means weaker cartels and less capacity to corrupt the judiciary and the police in Mexico with crumpled bills in brown envelopes. Crimes like extortion and kidnappings are also more easily tackled. …
Mr Shirk puts it this way. If you ask enforcement folk how large a dent their interdiction efforts – seizures, arrests, helicopter raids and so on – actually have on cartel earnings, they will say between 5 and 10 per cent. But just a few states embracing legal cannabis may end up robbing them of two to five times that amount.
In other words, when you reduce demand for an illegal product–in this case, by offering a legal alternative–you reduce illegal behavior associated with the marketing of that product.
Since cannabis is less harmful than alcohol or tobacco, regulating its sale and taxing it–rather than criminalizing its use– would appear to be a win-win.