The Mexican government took an unprecedented step this January when it integrated Michoacán-based fuerzas autodefensas, or vigilante groups, into its existing law enforcement structure, essentially legalizing them. Michoacán is one of many Mexican states that is controlled by drug cartels; the cartels often strongarm locals into giving them money and goods.

The vigilante groups allegedly formed in self-defense when federal forces were unable and unwilling to combat cartel violence and extortion. Fox News Latino reports that armed Michoacán vigilantes number over 20,000. By government edict, these many thousands of volunteer forces are part of the Rural Defense Corps, a newly revived program.

Prior to their inclusion as government-sanctioned forces, the vigilantes had cleared a number of towns of cartel presence, including Paracuaro, Antúnez and Nueva Italia. According to a Time magazine correspondent, taking back towns usually included one to three hours of gunfights.

Michoacán vigilante groups battle primarily against the Knights Templar, one of the eight main groups that controls Mexican drug trafficking. Since the vigilantes joined government law enforcement, they’ve already had a major triumph: the capture of one of the main leaders of the Knights Templar, Dionicio Loya Plancarte, also known as El Tio. Loya Plancarte had a $2.2 million bounty on his head, and his detainment may crumble the Knights Templar alliance.

CBS reports that the Michoacán vigilantes have sided with or been infiltrated by the New Generation cartel, a rival of the Knights Templar cartel. The Christian Science Monitor notes that most vigilante actions do not follow humanitarian procedures; instead, they mostly follow their own agenda of justice.

The vigilantes’ approach toward drug cartels, though arguably successful, was not initially endorsed by the Mexican government. Last month, according to CNN, the federal government demanded that the vigilantes end their crusades.

Only two weeks later, the Mexican government allowed for the vigilantes to legally serve alongside Mexican soldiers against drug cartels.

According to the BBC, vigilante groups will not stop fighting until the leaders of the cartels are captured. Most vigilantes are ranchers, farmers, and blue- or white-collar workers. Fox Latino reports that the vigilantes have been allowed to carry assault weapons that ordinary citizens are not.

Mexico has suffered from the violent and abundant presence of drug cartels, especially since the 1990s when Mexican cartels rose to fill the power vacuum created when Colombian cartels declined. Cartel firepower and government corruption have stopped the Mexican federal government from controlling cartels. In many cartel-controlled areas like Michoacán, victimized civilians who were tired of government inaction formed vigilante defense teams, and have actually seen success in expelling cartels where the government has failed.

The tide of vigilante justice has drawbacks as well as benefits. Their very existence, the Christian Science Monitor says, is a double-edged sword for the federal government – if it doesn’t support the vigilantes, then it supports the cartels by default. However, if it condones the vigilante groups, it appears to support uncontrolled paramilitary forces.

The problem of removing cartels is not just a matter of chasing them out of a few towns. Part of the battle that the government has faced is the depth to which the cartels control day-to-day life.

CBS reports that in Apatzingan, a city and municipality within Michoacán, cartel hitmen burned down a pharmacy to establish their dominance, and the Associated Press reports that the Knights Templar control parts of Michoacán iron ore mining trade in order to get chemicals from China.

The situation is still in flux, and cartels still control billions of dollars worth of drug traffic. The Michoacán vigilantes and their new federal allies will have a long road ahead of them before they can claim complete victory.