Militias are significant factions in control of criminal activity in favelas. They are armed groups comprised of individual with a certain degree of public power, who coerce inhabitants and traders using force and terror in order to dominate particular regions of the city.

They are motivated by personal profit and legitimize their presence with arguments about protection and liberation of communities from drug trafficking.

in some cases the militia have succeeded in expelling traffickers from strongholds in the city, and have subsequently charged residents and businesses 'safety' taxes. They also charge for the distribution of gas and illegal cable TV, referred to as 'gatonet', alternative transport and over-priced goods.