Gang and government lawlessness plague Mexico. On Sept. 26, a violent gang and a criminal government combined to massacre 43 students near the Guerrero state town of Iguala.

A perceived attitude of elite indifference by Guerrero state and federal government officials has fanned national outrage. Now, as demonstrators block the runways of Acapulco's airport and protests over gang-government collusion spread, Mexican President Enrique Pena Nieto faces an expanding crisis of confidence in government institutions.

There are two reasons the crisis could damage Pena's own ability to govern.

Reason no. 1: Atrocities far less hideous and institutionally debilitating than the Iguala Massacre have sparked mass revolt. This column's first sentence sketches reason no. 2: Mexican government corruption facilitates organized crime. Organized crime enriches a corrupt political class. Cartel gunmen and crooked cops on the streets, cartel comandantes and corrupt politicos through institutions ensnare the Mexican people.

The Iguala Massacre captures Mexico's dilemma in one vicious incident.

Here are the barbaric facts. On Sept. 26, Iguala municipal police broke up a march and a political demonstration staged by student protestors. Police killed six and then arrested another 43 student protestors. The police killed perhaps another dozen (by "asphyxiation," investigators believe) and then handed the others over to the Guerreros Unidos (United Warriors) gang. The gangsters killed the other 30 or so young men and women, shredded their corpses and burned the remains. After two gang members confessed in late October, investigators found burnt bone fragments in a dump near the town of Cocula (17 kilometers from Iguala). Search parties also discovered six bags of human remains.

Yes, policemen and gang gunmen colluding to commit mass murder. The tragedy, however, has a Lady Macbeth turn, which leads to Guerrero's governing elites.

In early October, residents of Iguala claimed that Iguala mayor, Jose Luis Abarca, pressured by his wife, Maria de los Angeles Pineda, ordered municipal police to attack the students. Pineda intended to run for mayor of Iguala (to replace her husband after he completed his term). Pineda, whom local media call "Lady Iguala," had scheduled a speech before 3,000 bused-in supporters in the city plaza. She told her husband opposition demonstrators must not interrupt her campaign fiesta.

Pineda, the sister of two deceased members of the Beltran-Leyva cartel, is emblematic of government and gang in one well-heeled elite. Several Guerreros Unidos gang members were once Beltran-Leyva gunmen. National media now call Pineda "the First Lady of Murder."

As September ended and October progressed, investigators discovered several mass grave sites — incriminating discoveries, but none of them contained the students' bodies. Fear of a cover-up to protect crooked cops and politicos spurred protests throughout Guerrero state. Mayor Abarca is a powerful member of the hard-left Party of the Democratic Revolution. Protestors claimed that the state governor, Angel Guirre (another PRD bigwig), was conspiring with Abarca to frustrate the search.

Anyone shocked to learn that Guerrero's murderous elites belong to Mexico's left-wing socialist people's party?

Federal police joined the investigation and arrested 24 Iguala policemen and gang members. Meanwhile, Abarca and Pineda fled. On Oct. 19, federal police assumed all local police duties; on Oct. 22, federal prosecutors issued arrest warrants for Abarca and Pineda. That same day, Aguirre resigned as governor of Guerrero.

Nov. 4: A special federal police unit arrested Abarca and Pineda. The upscale-leftists had holed up in Mexico City's working-class Iztapalapa district.

Kudos for the feds? Not quite. A comment by Mexican Attorney General Jesus Murillo Karam (made in a Nov. 7 press conference discussing the crimes) inflamed passions and undermined President Pena's claim that his government was focused on bringing the murderers to justice. Murillo Karam decided that he had taken enough questions and told reporters "Ya me canse" ("Enough; I'm tired.") Several million citizens heard this as elitist arrogance.

Critics throughout see the Abarca-Pineda duo's involvement as prima facie evidence of the political class' disdain for the rule of law. For many Mexicans, Pena's own Institutional Revolutionary Party is a synonym for corruption and disdain.

AUSTIN BAY, a Washington Examiner columnist, is nationally syndicated by Creators Syndicate.