Clockwise from bottom, José Santiago Valencia Sandoval, his daughter, 11-year-old Bianca, wife, Blanca, and 14-year-old son Bernabe at their home during an interview with The Washington Post last month. The Valencia family was killed on the way home from the family's ranch. (Dominic Bracco II/Prime for The Washington Post)

MEXICO CITY — We saw his kids first and broke out laughing. You couldn’t look at their angelic, chubby, giggling faces without smiling. They could barely see over the dashboard of the red truck they were driving.

And yet these two boys, José Santiago Perez, 16, and Bernabe Perez, 14, were the emissaries the ex-drug cartel henchman had sent to fetch us.

Dominic Bracco, a photographer, and I met the kids last month in a dirt lot outside a corral in the Mexican state of Michoacan. We were there to write about a citizen militia that formed to drive out a drug gang but was turning into something more sinister.

Their father, José Santiago Valencia Sandoval, had experienced both sides of this conflict. He had worked for the Knights Templar cartel, then defected to join the militia when it started in the little hillside town of Tepalcatepec more than a year ago. He agreed to meet.

After so many years and tens of thousands of deaths, the drug war still casts a long shadow over Mexico. Whole swaths of the country — the states of Michoacan and Tamaulipas, the cities along the U.S. border — live by the rules of cartels that now do far more than transport drugs. There is the anxiety of random violence, the frustration of forced cartel taxes, the fear of kidnapping or worse.

In his first year in office, the new president, Enrique Peña Nieto, wanted to change Mexico’s image from a country at war to a rising economic power. But it wasn’t long before he reverted to deploying soldiers to patrol streets where the main authority has been the mafia’s teenage spotters with their two-way radios. In these places, where the police can be more dangerous than the outlaws, and politics and crime go hand in hand, there is little hope that Mexico’s enduring curse is ending. In this world of shifting alliances, it is hard to know what to believe or whom to trust.

Like his kids, Valencia was not what I was expecting. He was training a prancing horse and listening to ranchero music when we pulled into his yard. In his living room, decorated with his hunting trophies, he cracked open beers and told amazing tales in his breezy way: how he faked his own death by pouring red paint down his neck to elude an assassin. How he recorded himself in a video tell-all he planned to have sent to the Drug Enforcement Administration in the event of his murder.

Last week, that day arrived.

Bernabe, 14, was killed along with his father, mother, sister and brother. (Dominic Bracco II/Prime for The Washington Post)

Valencia and his wife, Blanca, the two boys and his 11-year-old daughter, Bianca — who had all fed us tacos and hosted us generously at their home — were stopped while they were driving in their red truck in the neighboring state of Jalisco. The YouTube videos taken later show the vehicle littered with bullet holes. The attorney general’s office reported that there were signs of torture on the corpses. Nobody survived.

When we met him, Valencia had not seemed fazed by the dangers he faced, but he was serious about the problems in his home town. He felt the militia movement that has spread across Michoacan — supported by the Mexican government — was being corrupted by the New Generation drug cartel out of Jalisco. The group he had joined, he said, was becoming a front for criminals and could end up as rotten and abusive as the cartel he had left.

“I do not tolerate injustice, and I am not going to represent something that I am fighting,” he told us. “I want to send that message through the media.”

He knew he was a target.

“We feel threatened by certain people within the movement,” he told us.

About three weeks after we published our story about him, Valencia called our office in Mexico City. By then, I had become Facebook friends with his sons. I noticed that their hobbies and photos reflected the environment that had raised them: José’s profile picture was a black SUV with tinted windows, his younger brother’s a high-powered rifle.

Both Dominic and I were traveling, and Valencia left messages that he had something “good” to show us. When pressed for details over the next few days, he mentioned he had a recording of the mayor of his home town, Tepalcatepec, that showed all the “trash and corruption of the government.” The next time we went to Michoacan, he told our office manager, we needed to visit him.

We called him back when we returned to Mexico City. He didn’t answer his phone. And then we noticed his name.

José Santiago Valencia Sandoval with his armored vehicle, which he confiscated during a battle with the Knights of Templar cartel. (Dominic Bracco II/Prime for The Washington Post)

The killing of Valencia and his family merited barely a blip in the news of Mexico. But for us it felt tragic and disorienting. Had the article put him in greater danger? Had he been killed because of the recording he was trying to release? He had betrayed a drug cartel (one he told us he served against his will) and presumably had many enemies. Had his luck simply run out?

And why kill the children?

Dominic wrote in an e-mail to me after this that “the real tragedy is that it had seemed he was finally escaping this life through the self-defense groups, but it turned out that they were becoming their own mafia — or well on their way. Later he set out trying to let people know, as a way to fix this place.”

Most murder cases in Mexico are not solved. Relatives of the victims must live with their questions. On his couch at home, with his sons tumbling all over him, Valencia told us that he hoped speaking out would make people “correct their ways.” If they didn’t, he said, “I’m going to call you and give you first and last names, to send into the light of the world.”

Now his name is in the sunlight. And theirs live on in darkness.

Dominic Bracco and Gabriela Martinez contributed to this report.