Is Legal Pot Crippling Mexican Drug Trafficking Organisations? The Effect of Medical Marijuana Laws on US Crime

I abhor marijuana and the other drugs, but I am not blind to information that seems to confirm what libertarians keep saying for decades:

Gavrilova, E., Kamada, T. and Zoutman, F. (2017), Is Legal Pot Crippling Mexican Drug Trafficking Organisations? The Effect of Medical Marijuana Laws on US Crime. Econ J. doi:10.1111/ecoj.12521

Abstract: We show that the introduction of medical marijuana laws (MMLs) leads to a decrease in violent crime in states that border Mexico. The reduction in crime is strongest for counties close to the border (less than 350 kilometres) and for crimes that relate to drug trafficking. In addition, we find that MMLs in inland states lead to a reduction in crime in the nearest border state. Our results are consistent with the theory that decriminalisation of the production and distribution of marijuana leads to a reduction in violent crime in markets that are traditionally controlled by Mexican drug trafficking organisations.