Private militias have provided criminal groups with greater mobility and fighting power, enabling them to engage in large-scale violence and seek control of criminal markets and territories beyond their home towns. The Mexican case highlights the need for democratic elites to reform authoritarian judicial and security institutions and to punish state agents who protected organized crime, in order to prevent the intertwining of democratic politics and the criminal underworld.

The spread of subnational party alternation in states with drug trafficking routes and the proliferation of private militias led to the outbreak of intercartel wars. The development of private militias allowed cartels to contest their rivals' control over drug trafficking territories, leading to largescale criminal violence.

political alternation and the rotation of parties in state gubernatorial power undermined the informal networks of protection that had facilitated the cartels' operations under one-party rule. Without protection, cartels created their own private militias to defend themselves from rival groups and incoming opposition authorities.