The video begins with an establishing shot of sorts: A Mexican flag dangles from a flimsy pole—a fishing rod, maybe—that somebody has stuck in the dirt in the foreground. Beyond we see the back of a man in a yellow shirt standing on the gently sloping bank of a river that is just catching the last of the late-afternoon light. He is standing perfectly still, watching a boat perhaps 150 feet away from him, near the steep, carrizo-covered opposite bank. It’s an eighteen-foot aluminum airboat with a low deck and an enormous motorized fan on the rear that emits a deafening roar. The camera zooms in on the boat, which is pointed upstream, holding its position against the considerable current. The light is not great, and neither is the focus, but we can just make out the white shirtsleeves of the driver, and perhaps the outline of another man seated on a small bench in the front of the boat, along with the familiar green stripe of the U.S. Border Patrol on the boat’s silver profile.

We hear an unseen woman’s voice—the filmmaker—rising above the drone. “He is taking aim, right? At them?” she says in Spanish. There is a muttered reply from nearby. The camera pans left, and we are now looking out from behind the windshield of a parked truck—our videographer has been sitting in the front seat all along, filming through the open window on the passenger side. Now we can see people on the riverbank having a barbecue: A middle-aged man in a yellow baseball cap and long white shorts is leaning idly against a white Buick sedan. A skinny young man in a muscle T squats at the man’s feet, while another stands nearby. A woman sits on the hood of the car, looking placidly down at the river. A girl, maybe ten, in an orange tank top ducks into one of the Buick’s rear doors, reaching for something, while another, slightly younger, walks away from the car, swinging her arms back like she is getting ready to skip, or perhaps execute a standing broad jump. 

There are dragonflies in the air, and everyone is moving in that lazy way you do on a summer evening, after the food and the beer are mostly gone but the lingering sun keeps people from going home. It would be a pleasant scene but for the steady roar of the airboat. The man in the yellow hat, who has only a few more minutes to live, turns to greet someone who has just walked up. “Ya quítala,” we hear the filmmaker’s companion say. “Turn it off.”

When the camera comes back on, everything is different. Instead of the steady drone, the airboat’s motor is revving wildly. Suddenly our filmmaker leaps out of the truck and runs toward the water, the camera pointed down at the gravel beach and bouncing wildly with each step. It sounds like we are at a NASCAR race now, the boat has gotten so loud, yet the camera stays pointed down, maddeningly averted from whatever commotion is drawing us to the river. Just as we pass a white plastic picnic table with a blue cooler next to it, we hear the shots: seven of them in quick succession, each one sounding on the camera’s cheap microphone like the ka-chunk of a heavy-duty stapler. The gunfire makes our filmmaker stop, finally, and bring the camera up before her.

We see the aftermath. Down by the river there are a dozen or more people screaming and crying. The man in the yellow ball cap is lying on his back about ten feet from the water. A woman stoops over him, wailing. “That’s against the law! That’s against the law!” someone can be heard screaming in English. The boat circles once and seems to stop at the far bank momentarily, before speeding away upstream.

The man in the video was a 37-year-old bricklayer named Guillermo Arévalo Pedraza. He was shot in Nuevo Laredo on September 3, 2012, during a visit to the river with his wife, Nora Lam Gallegos; their two daughters, Mariana, who was nine, and Priscilla, who was ten; and several friends. The shooting took place in a popular park called El Patinadero, where families come on weekends to swim, fish, and relax at the barbecue pits and picnic tables. Arévalo’s wife and daughters all had late-summer birthdays, and Arévalo had cooked a carne asada as a kind of collective celebration. It was a Monday night, and the park was not crowded, though several other families, some with children, were picnicking nearby. The Border Patrol airboat appeared after Arévalo and his family had eaten and the party was winding down. Interviews conducted by the Tamaulipas state police and depositions collected from witnesses by Lam’s American attorney all tell the same story about what happened next, during the missing portion of the video. Shortly after the boat appeared, a young man jumped out of the carrizo on the Texas side of the river, plunged into the water, and began swimming toward the park. Before he could make it, though, the airboat circled him in midstream, while an officer in a black face mask tried unsuccessfully to grab him.

A small crowd soon formed by the side of the river, as people in the park became aware of the chase. They began shouting at the agents to stop circling the swimmer, who by now had been in the water fighting both the current and the boat’s heavy wake for some time. The beach was strewed with small rocks, and one witness reported that one or two men—though not Arévalo—threw rocks at the boat but failed to connect, because the boat was too far away. (Five other witnesses reported that no rocks were thrown.) Eventually the swimmer managed to get past the boat. Just as he was about to reach the safety of Mexican soil, the masked officer in the front of the boat suddenly dropped to one knee and fired his assault rifle at the crowd, hitting Arévalo in the thigh and the chest. “They killed him! They killed him!” his wife screamed in Spanish. His younger daughter, Mariana, had been standing next to him when he was shot, and she was in all likelihood the only person who reached him before he died. She hugged him as he lay on his back, bleeding. She was so covered with blood herself, her mother said later, that she looked like she too had been shot, as she easily could have been.

Among the witnesses at the park that evening was an American named Veronica Martinez, who worked as a nurse in Laredo but kept a home in Nuevo Laredo as well. Knowing she was an American, friends urged her to cross the bridge immediately and report what she had seen. There was no doubt in her mind, Martinez said later, that what she had witnessed was a completely unprovoked killing. Her boyfriend drove her to the nearest bridge, where she bypassed the line of pedestrians waiting to cross over and demanded to speak to someone in charge. She was interviewed by a Border Patrol supervisor and an FBI agent in a small room on the American side of the bridge. The next day, the Border Patrol issued a statement announcing only that agents in an airboat had been attacked with rocks and had used their weapons to defend themselves. There was no mention of the fatality or the victim, and the agents were not named. Newspapers and TV stations in both Laredo and Nuevo Laredo reported on the shooting on September 6, and Arévalo’s widow told reporters that the Border Patrol had killed her husband, a claim that the agency would not verify. 

The incident would likely have remained in the shadows, except that the next day the video described above—which had been made by an anonymous bystander—found its way into the hands of producers at a news organization called RN Noticias, in Nuevo Laredo. Soon after, the station posted it on YouTube, and everybody in Laredo and Nuevo Laredo could see the tragedy, or at least its aftermath, in living color. Television news all over Mexico picked up the story, and the video was shown again and again.

In Mexico, alleged Border Patrol malfeasance is a popular genre on YouTube, and there are plenty of videos that purport to show human rights violations. In this case, however, the shocking abruptness of the violence and the immediacy of the grief on display gave the video a singular impact. A few days after it was posted, a Mexican senator denounced the shooting on the floor of the Mexican congress and called for a full investigation. On September 11, Mexican president Felipe Calderón brought up the incident during a visit to the offices of the Wall Street Journal, in New York, where he sat down with the editorial board for a wide-ranging interview. “This father was not trying to cross the border, he was trying to pass a good day with his kids,” Calderón told the board, adding that this was only one of several recent shootings of Mexicans by U.S. agents. The Journal was careful not to condemn these shootings but did offer an interesting observation about how such events are perceived in the United States. Everybody had heard of Brian Terry, the Border Patrol agent whose 2010 murder had become entangled in the botched “Fast and Furious” gun-running sting, the Journal opined. But who has heard of Guillermo Arévalo Pedraza? 

Over a year and a half later, the answer to that question, at least in this country, is still “almost nobody.” The Border Patrol has released no official report on the incident, not even so much as the name of the shooter. Nor has there been any official announcement by federal investigators. Contacted for this story in late March, an FBI spokesperson would say only that the agency had completed its investigation and turned its findings over to the Civil Rights Division of the Department of Justice. In recent months, however, the Border Patrol’s use of force has come under heightened scrutiny both in Congress and in the national media, casting a new light on Arévalo’s shooting and others like it. Border security, meanwhile, has once again become a buzzword in Washington, as a new immigration reform bill wends its way through Congress. As some in Washington call for more agents in the field as a prerequisite to negotiation on any comprehensive reform measure, Arévalo’s case poses a troubling question: While agents watch the border, who is watching them?

Border patrol shootings, especially those that involve agents shooting across the border into Mexico, used to be quite rare. Such incidents have become more common, however. Since the beginning of 2005, Customs and Border Protection officers, who work at ports of entry, and Border Patrol agents, who police the vast areas between ports, have killed at least 42 people. Some of these shootings were clearly justified, but in many instances, as in Arévalo’s case, accounts offered by agents and eyewitnesses differ. The best known of these incidents was the June 2010 shooting of a fifteen-year-old Mexican boy under a railroad trestle connecting El Paso and Juárez. Sergio Adrián Hernández Güereca was among a group of boys and men who had crossed the mostly dry, concrete-covered bed of the Rio Grande, only to be surprised by a Border Patrol agent on a bicycle. A cellphone video shot from the sidewalk on the nearby international bridge captured what happened next. In the video, the agent manages to collar one of the fleeing young men, and then, holding his captive down with one hand, he points his pistol across the river and fires. A figure falls dead, shot in the head. 

The agent, Jesus Mesa Jr., would later tell investigators he was surrounded by rock throwers and fired in self-defense. Yet the video, which has now been viewed more than 1.6 million times on YouTube, clearly shows that Mesa was not surrounded. And while it seems to show more than one person throwing rocks at the agent, Hernández himself, who was hiding near one of the trestle’s pilings, was not among them. Federal investigators declined to prosecute Mesa for the shooting, finding that he had followed agency policy.

Far fewer people have viewed the video of Arévalo’s killing, though both incidents raise the same essential questions about how lethal force is being used along the border, especially with respect to incidents of alleged rock-throwing attacks on agents. Border Patrol agents and CBP officers both work for an agency called Customs and Border Protection, which is a division of the Department of Homeland Security. Official CBP policy allows agents to use lethal force when they feel their lives are in danger, and while the agency for years has declined to make public the details of this policy, senior officials have long maintained that the agency considers rock-throwing attacks (or “rockings,” as agents refer to the incidents) to be potentially life-threatening situations. Rockings can be dangerous, T. J. Bonner, the former president of the National Border Patrol Council, the union that represents agents, told Homeland Security Today magazine in 2011, not just because of the damage a thrown rock could cause but also because of what could happen after an agent was incapacitated by a rock. “What’s to stop one of these people,” he said, “from then taking the agent’s firearm and executing him?” 

Statistically speaking, Border Patrol agents are much less likely to be physically assaulted than municipal police officers in an average city. Killings of agents are rare, though not unheard of; three agents have been killed by assailants since 2004. There is no question that rockings have become common, however, due in part to the sheer number of agents that are now on the border. In the post-9/11 era, a renewed focus on border security led to a doubling of the force (there are now roughly 21,000 Border Patrol agents, along with nearly 22,000 CBP officers working the ports of entry). Smuggling of both people and contraband has become more difficult as a result of the massive increase in personnel, and rock-throwing has become a favored means of distracting agents trying to make arrests. This is especially true in urban areas, where smugglers and agents are ubiquitous. Sometimes the rock throwers are lookouts, hired to buy their employers a few extra seconds to get back into Mexico. Other times they are simply bystanders who express their displeasure with la migra with whatever means they can find at hand. 

No agent has ever been killed by a rock, and injuries are infrequent, usually because of the distance between agents and their assailants. The vast majority of these attacks do not result in agents’ firing their weapons. Still, it’s clear that agents are using their weapons with some regularity. According to numbers compiled by the inspector general’s office of the Department of Homeland Security, agents were attacked with rocks 185 times in 2012, the most recent year for which figures are available, and responded with firearms in 22 of those instances. In a year-long investigation of CBP shootings published in December, the Arizona Republic found 8 instances in which agents had killed rock throwers since 2010. Using agency records, the Republic also tabulated 160 incidents during that period in which agents chose to use less-lethal weapons at their disposal, including a type of military-grade paintball gun that can shoot more than ten pepper spray–filled balls per second. There were no reported injuries—among agents or assailants—in those instances, and agents consistently reported that these weapons were quite effective in deterring rock throwers. Yet agents are not required to carry them, even in urban areas, where most rockings occur. 

Under pressure from members of Congress concerned about the rash of recent shootings, in 2012 CBP officials quietly invited a group of law enforcement experts to review the agency’s use-of-force policy. The group, known as the Police Executive Research Forum, was given access to several years’ worth of internal CBP use-of-force incident reports. The CBP did not release the results of that review to the public, but some of its recommendations were leaked. The Associated Press reported last November that among other things, PERF advised against using lethal force on rock throwers. A better policy would be to move out of range or use less-lethal weapons, PERF concluded. In response to questions from the Associated Press, however, Border Patrol chief Michael Fisher announced that his officers would continue to employ deadly force against rock throwers at their own discretion, despite the experts’ recommendation. This prompted a round of stories with unfortunate headlines like “Border Patrol Will Continue Killing People Who Throw Rocks.” The agency seemed oblivious to the public relations implications, or perhaps impervious to them.

That changed in late February of this year, when the Los Angeles Times acquired an unredacted version of the PERF report. According to the Times, the report determined that “some border agents stood in front of moving vehicles as a pretext to open fire and that agents could have moved away from rock throwers instead of shooting at them.” The report also suggested that some agents fired their weapons at rock throwers out of frustration, not a sense of endangerment. Finally, it cited a “lack of diligence” on the part of CBP officials assigned to investigate agent-involved shootings. Asked about the report, Jeh Johnson, Barack Obama’s new Secretary of Homeland Security, replied that the agency was rethinking its recalcitrant response to PERF’s recommendations.

Then, in early March, Chief Fisher announced official changes to the Border Patrol’s use-of-force policy. Agents would now be prohibited from stepping in front of moving cars or shooting at vehicles fleeing from agents and would be instructed to move away from rock throwers or take cover if possible. This was widely described as a “reversal” of previous policy, but it remains far from clear what practical effect it will have on the ground. After all, the existing use-of-force policy, which CBP finally made public around the same time, also directed agents to use lethal force only when they felt themselves to be in imminent danger. Indeed, officials with the National Border Patrol Council immediately downplayed the significance of the announcement, which Chief Fisher himself had referred to not as a new policy but as a clarification of existing policy. 

“We don’t view it as an outright restriction on agents’ use of deadly force,” Shawn Moran, the vice president of the agents’ union, told the Arizona Republic on the same day Fisher made his announcement. Moran characterized it as “a reminder to agents to seek alternatives.” In other words, agents will still exercise their own discretion in deciding when to shoot at rock throwers. And the new directives have yet to be incorporated into an official update of the use-of-force handbook, a process that is typically the result of a protracted negotiation with the union, which relies on the handbook in defending agents subject to disciplinary actions. “We would fight any restrictions on the ability of agents to use force to defend themselves,” Moran told the Republic.

Whether or not agents will be held accountable for the decisions they make remains unclear as well. Neither Chief Fisher nor Secretary Johnson has publicly responded to one of the key findings in the PERF report, concerning CBP’s “lack of diligence” when it comes to internal investigations. The Arizona Republic’s investigation examined the 42 lethal shootings since 2005, and in not one of those cases could the paper determine that any agent involved had ever been disciplined by any agency, charged criminally, or found civilly liable. The silence surrounding the investigation of Guillermo Arévalo Pedraza’s death is not the exception, it’s the rule. 

“Affairs on the border cannot be judged by standards that hold elsewhere,” Walter Prescott Webb wrote in The Texas Rangers, his 1935 treatise on the state’s elite police force, which was for all practical purposes the frontier’s nineteenth-century version of the Border Patrol. Almost eighty years later, the modern Border Patrol still seems to operate in a kind of moral and ontological gray area, one that extends to even the most basic question of just what a Border Patrol agent is. An agent is not technically a soldier, though casual observers could be forgiven for thinking otherwise. Not only have the accoutrements of war become increasingly common on the border, as the CBP uses drones and Black Hawk helicopters to patrol the more remote areas, but the rhetoric of war is pervasive in the media and on Capitol Hill. In 2010 Oliver North took his Fox News War Stories team to the border to report on what he called the “Third Front” (the other two being Iraq and Afghanistan). The National Geographic Channel reality show Border Wars, which follows Border Patrol agents in the field in the tradition of Cops, is now in its eighth season. Meanwhile, the violent conflict in recent years between warring cartels in northern Mexico has given rise to the “spillover violence” meme, which has been ubiquitous in policy circles and media reports since 2008. Security hawks in Congress argue that the Border Patrol—only recently doubled in size—needs reinforcements to protect us from this phenomenon, despite the fact that the Southwest border remains among the safest places to live in the United States. (El Paso, despite its proximity to Juárez, one of the most dangerous places in the western hemisphere, is the safest large city in America.) 

Policymakers and senior officials at the agency seem torn about whether the Border Patrol is an army or an enormous police force. The seeds of this identity confusion were planted shortly after 9/11, when the Border Patrol was subsumed under the newly created Department of Homeland Security and recast as one of many regiments in the nation’s war on terrorism. The Border Patrol’s new mission was said to be aligned with that of the Army or the Navy or the NSA: to protect us from foreign invaders bent on our destruction. But while having 21,000 agents on or near the border no doubt has dissuaded some foreign elements from entering the country overland, fighting terror is not principally what those agents do. The Border Patrol arrested 364,000 people in 2012. Not a single one was an international terrorist. The vast majority were migrants in search of jobs. An agent spends most of his or her time chasing would-be nannies, construction workers, and landscapers. Even the drug mules, los mochileros, are not generally armed or dangerous.

The difference between a soldier and a police officer is more than a semantic one, and the Border Patrol’s identity crisis has genuine consequences. War and police work are fundamentally dissimilar, explains Christopher Wilson, a border-security expert at the Woodrow Wilson International Center for Scholars, a Washington, D.C., think tank. “When you’re told your mission is national security, and the people you’re interacting with are not citizens—meaning they’re not the people you’re accountable to in a democratic structure—that does replicate to a certain extent the situation the military faces,” he said. “Nonetheless, they are law enforcement. And what that means is you use the minimal force needed to do your job.” 

Police forces are also more transparent and receptive to criticism from the communities they serve than armies. The community the Border Patrol operates within may be an unusual one, in that it straddles an international boundary, but it is a community nonetheless. The ties—family, cultural, and commercial—that bind twinned border towns like Laredo and Nuevo Laredo are hundreds of years old. Yet the metaphor of war has, perhaps unintentionally, helped give the CBP a certain measure of insulation from that community. Extracting information from the agency about a shooting is notoriously difficult, especially when compared with a typical urban police department. If an officer kills someone in Dallas, for example, the name of the officer involved is typically released the same day, and residents of Dallas can expect to see a statement describing what happened from the chief of police in the paper or on the evening news. Internal investigations follow a standard operating procedure that is reasonably transparent. The result is that while community members may not always agree with decisions made about the legitimacy of police shootings, the process at least offers some reassurance that officers are accountable to the community they serve.

The Border Patrol, by contrast, almost never releases the names of agents involved in shootings or the results of internal investigations. Typically, such details become public only if a civil suit is filed and a judge grants the attorney for a victim’s family access to the relevant information. Information about shootings is very hard for the media to acquire as well. In its investigation, the Arizona Republic noted that it took nearly a year for the agency to release the use-of-force reports the paper requested, and they were frequently heavily redacted or incomplete. 

Members of Congress, even those whose duties include oversight of CBP, have the same difficulties when it comes to getting information from the agency, according to El Paso congressman Beto O’Rourke, a Democrat who sits on the Homeland Security Committee. “The top officials cloak themselves in the national security mantle,” he said. “We can’t get any more information than anybody else about specific incidents.”

With such an opaque internal disciplinary process, victims’ families often find that their only recourse is through the courts. But this is frequently less than satisfying too. A Corpus Christi trial lawyer named Bob Hilliard represents the families of both Sergio Hernández and Guillermo Arévalo. “Hernández was not throwing rocks. And I don’t think Arévalo was either,” he said. “But what if they were? Would a Laredo police officer shoot somebody dead for throwing a rock at him from a hundred feet away?” 

Hilliard’s wrongful-death suit on behalf of Hernández was dismissed by an El Paso judge in August 2011 on the grounds that the victim was not killed in the United States and therefore not entitled to relief under the U.S. Constitution. “If I understand that correctly, it means any agent can do anything he wants to anybody as long as the victim is in Mexico and the agent is on U.S. soil,” Hilliard said. “Does that sound right to you?” Hilliard has appealed the ruling. His suit on behalf of Arévalo has yet to be filed.

Whether criminal charges will be brought against Arévalo’s shooter is still an open question. For federal prosecutors, when it comes to filing charges against Border Patrol agents, there is more to consider than just the facts of the case. The appointment of U.S. attorneys, after all, is overseen by the president, and, rightly or wrongly, they are seen as his agents, which means such prosecutions inevitably become entangled in the seemingly endless debate over immigration reform. Consider the notorious case of Border Patrol agents Ignacio Ramos and José Compeán, who were tried and convicted in 2006 for shooting a fleeing, unarmed smuggler. The smuggler survived and escaped to Mexico, where his account of the shooting led to the agents’ eventual prosecution. Investigators discovered that the agents, knowing they had committed a crime, covered up the episode by destroying evidence and lying about the incident. Nevertheless, the reaction to their sentencing, especially on conservative talk radio, was so vehement that then-president George W. Bush was persuaded to commute their sentences as one of his last acts in office. How could we be going after agents, it was argued, when officials in Washington had done so little to stem the flow of illegal immigrants and narcotics?

It did not help, of course, that the victim in that case was a smuggler, a fact that is not lost on federal officials in Hernández’s case either. Three days after the teenager’s death, authorities leaked his arrest record to the press. At a time when we still did not know the name of the shooter, we knew that Hernández was a patero, a smuggler who helps people cross the border. He had been arrested for allegedly helping people illegally cross more than once, most recently in 2009. (He was never prosecuted, probably because he was a minor.) Leaking Hernández’s record was a violation of federal law—juvenile records must be kept private—but the agency was facing a public relations disaster. When asked about Hernández’s record on Fox News, Hilliard replied with a question of his own: “And punishment for [smuggling] is for the Border Patrol agent to be judge, jury, and executioner there on the border?” 

No smears have been forthcoming about Arévalo, whose name does not appear in CBP’s database of offenders. Still, Hilliard said he is not optimistic about a criminal prosecution. Border security is still a top issue, especially for Republican primary voters, which means it remains a political football. He thinks U.S. attorneys learned a lesson from the Ramos and Compeán prosecution. “It’s just not worth the hailstorm that will follow,” he said. 

To date, neither the House nor the Senate Homeland Security committees have scheduled hearings on CBP’s use-of-force policies, though incoming CBP commissioner Gil Kerlikowske, a former Seattle police chief, was asked about the issue at his confirmation hearing in January. He promised more openness if confirmed, noting that he had never worked for a police department that did not make its use-of-force policies public. O’Rourke, the El Paso congressman, has teamed up with a conservative New Mexico Republican named Steve Pearce on a proposal to create a new border oversight commission, to bring some transparency to the agency’s activities. The bill would also create a new ombudsman within the Department of Homeland Security, to bring an independent set of eyes to bear on allegations of wrongdoing, not unlike the approach used by the U.S. military to address the recent sexual abuse scandals. O’Rourke has found some tea party members to be surprisingly receptive to his reform message. “They don’t like the idea of the border as a kind of Constitution-free zone, where civil liberties and constitutional protections don’t apply,” he said. 

Nora Lam Gallegos lives in a neighborhood on the northern outskirts of Nuevo Laredo called Lomas del Rio, one of the neatly gridded developments of modest concrete and cinder-block homes that have sprung up in the twenty years since the passage of NAFTA made this city a boomtown. On the February morning I visited, it was bitterly cold and overcast, and nobody was out on the street. I recognized the cheerful green exterior of Lam’s house from earlier reports on Mexican TV news, though it had lost much of its charm in the intervening months. Lam told me she had been able to find only sporadic employment since her husband’s death, including some part-time housecleaning. It was not enough to replace her husband’s income. The girls were not at home, but the hallmarks of female adolescence were hard to miss. On a shelf in the living room was a homemade Mother’s Day card, along with some Hello Kitty wonderama. Her daughters hadn’t been the same since seeing their father killed, she said. “They were never rebellious before,” she told me in Spanish, “but now they don’t want to listen.” The Tamaulipas state government paid for the kids to see a psychologist, which was helping, she said. The park where her husband was shot—part of a larger complex that includes a zoo, a skate park, and a swimming pool—had long been one of their favorite places to visit. “They are always asking me to go back,” she said, tearing up. “I take them, but not down to the river. I can’t do it.”

Lam, who is 28, would have celebrated her eleventh anniversary with Arévalo this year. They met at the wedding of a friend, and he made her laugh. He was a constant presence in the neighborhood, she said, playing soccer with the local kids or chatting at the fence with the neighbors. But mostly he lived for his daughters. After his death, Arévalo’s friends paid to have a corrido written about him, and the accompanying YouTube video is filled with still photos of Arévalo with Priscilla and Mariana, the girls mugging for the camera with a treat in one hand and an arm around their dad, who sports a goatee and a seemingly endless variety of major league baseball caps. Many of them were taken at El Patinadero, not far from the spot on the bank where he died.

Lam was interviewed by American officials in Laredo two days after the shooting, but she has not heard from anyone about the investigation in a long time. On the morning I visited her, the Laredo Morning Times carried a story about the sentencing of a Mexican gunman for the murder of Border Patrol agent Brian Terry. Terry’s killer, apparently a bandit who preyed on backcountry drug couriers, got a thirty-year sentence. I showed the clipping to Lam. “They made that Mexican pay for what he did,” she said. “And if my husband had been the shooter, instead of the one who got shot, you can be sure the Mexican government would have given him to the Americans, and he would have been punished.” But it didn’t happen that way. To this day, she still doesn’t even know the name of her husband’s assailant. “How come he is free and enjoying life,” she asked, “when there is no happiness in mine?” 

After I visited Lam, I went to the park where her husband died. The shocking images I’d seen in the video were hard to square with the scene itself. I stood in the parking lot of the zoo on the hill above the park and looked down at the acre of trees, their trunks painted white to ward off bugs, and the river beyond. A quarter mile up the opposite bank, in Laredo, sat a nice new H-E-B, its cobalt-blue-framed entrances beckoning cheerfully, its parking lot about a quarter full. Between the blacktop surrounding the store and the river below was a maze of bare-earth paths trickling down through mesquite and thick brush, beckoning the mochileros and pateros to take their chances. A white Border Patrol SUV was parked at a strategic point halfway down the bank, looking over the river and the park on the far side. It’s a favorite lookout point; if you study the satellite image of the park right now on Google Maps, you’ll see the same SUV, or one just like it. It’s a hell of a place to get shot in the chest with an automatic weapon, between an H-E-B and a zoo. 

I drove down to the river, where I was joined by Josué Ledezma, a close friend of Arévalo’s who was at the barbecue the day of the shooting. Ledezma is also a bricklayer by trade, though he is ten years younger than Arévalo, lean and handsome. He grew up in Lomas del Rio, and he and Memo, as Arévalo’s friends called him, had been close since Ledezma was a boy. In the video, he is one of the young men who can be seen near Arévalo as he leans against the white Buick, in the calm before the storm. 

Like everyone else in the city, Ledezma seemed to have been caught off guard by the freakishly cold weather. He was wearing pajama bottoms and a long-sleeved T-shirt, shivering as he walked me through the scene of the shooting. With his hands tucked snugly under his armpits, he showed me where he was standing when his friend was shot and how the bullets kicked up the gravel all around his feet. It was a miracle, he said, that only one person had been shot. He had dived into the brush when the shots were fired, and when he came out, he saw Arévalo lying on the ground. It was Ledezma who drove Arévalo to the hospital in his dying friend’s own Buick, along with his wife and daughters.

Ledezma said he had been contacted as recently as last fall about the shooting by American investigators and had told his story once again. After so much time had passed, however, he wasn’t optimistic that justice would be coming for his old friend. On the bank not far from where Arévalo died, there is a large square of concrete, the remnant of an old bridge or pipeline foundation, partially submerged in the river. In the days after his death, Arévalo’s wife had spray-painted a simple memorial there for her husband. It had read “Descansa en paz, El Memo.” Ledezma looked for it, but he couldn’t find it. It was definitely the same spot, but the words weren’t there anymore.

Se desvanecieron,” he finally said. “They faded away.”