For nearly a year and a half, U.S. government prosecutors in Arizona have sought to make an example out of Scott Warren. The 36-year-old geographer and border-based humanitarian aid volunteer was arrested with two undocumented migrants on January 17, 2018, and accused of providing the men with food, water, and a place to sleep over three days. A month later, a grand jury indicted him on two counts of harboring and one count of conspiracy, bringing the total amount time he could spend in prison — if convicted on all counts and sentenced to consecutive terms — to 20 years. Warren’s trial began in Tucson on Wednesday, marking the start of the most consequential prosecution of an American humanitarian aid provider in at least a decade. On Monday, assistant U.S. attorneys Anna Wright and Nathaniel J. Walters, who together have spearheaded an aggressive and controversial prosecutorial campaign against immigrant rights defenders in the Sonoran Desert, called their final witness to the stand. Over three and a half days of testimony, the prosecutors presented the jury with two Border Patrol agents who arrested Warren, a third who examined his phone, and some three hours of video-taped testimony from the young migrants he was arrested with, recorded before their deportations. The arresting agents provided little information beyond the bare facts of their operation as it unfolded, while the agent who testified about phone evidence seemed to paint a more incriminating picture of a man who was not charged in the case than he did of Warren. The migrants who were held as the government’s material witnesses described Warren as a figure who was hardly present during their short time in the U.S., beyond giving them permission to eat, sleep, and drink at a property he did not own, after they showed up with nothing but the clothes on their backs. The conspiracy charge in particular has cast an ominous pall over Warren’s case. As a prosecutorial tool, conspiracy charges can afford government attorneys sweeping powers in criminal cases. While the U.S. attorney’s office in Arizona was secretive about the nature of its theory of conspiracy with respect to Warren following his grand jury indictment, The Intercept revealed last month that the government considered Irineo Mujica, a prominent immigrants right advocate, a co-conspirator in the case. A dual U.S.-Mexican citizen, Mujica is the head of Pueblo Sin Fronteras, an immigrant rights organization known for its role in organizing the migrant caravans that have drawn President Trump’s outrage. He also operates a migrant shelter south of Ajo, the unincorporated community where Warren lives and works.

In opening arguments last week, Walters confirmed that the government considered Mujica a key figure in Warren’s alleged offenses. “They were in contact with Irineo Mujica,” the prosecutor told the jury, referring to 23-year-old Kristian Perez-Villanueva and 20-year-old Jose Arnaldo Sacaria-Goday, the Central American migrants, from El Salvador and Honduras, respectively, whom Warren was arrested with. Not only that, Walters said, Mujica had driven the pair to “the Barn,” a property used by humanitarian volunteers operating in the area. Warren’s relationship to Mujica was that of a “shared acquaintance,” Walters said, and cellphone evidence would show that the two were in contact before the migrants arrived at the Barn. Mujica declined to comment for this story and has not been charged with a crime.

Photo: Johan Ordonez/AFP/Getty Images

On Monday afternoon, Rogelio Velasco, a Border Patrol agent in the Tucson sector’s intelligence unit, testified about the government’s telephonic evidence, describing how his work excavating cellphones is used to support the agency’s high-priority cases, often executed by its plainclothes “Disrupt” units. “We try to look for bigger cases where more people are involved,” he testified. Warren was arrested by a Disrupt unit. Wright and Walters’ interest in Warren and the humanitarian groups he volunteers with, particularly the faith-based organization No More Deaths, began in 2017, when the assistant U.S. attorneys brought federal misdemeanor charges against several members of the group — Warren included — for leaving water and other humanitarian aid supplies on public lands where migrants routinely die. Velasco explained how, after Warren’s arrest, the prosecutors directed him to focus on particular date ranges and communications included in Warren’s phone and a phone carried by Perez-Villanueva. As the Border Patrol agent carried out the prosecutors’ request, he said he found a series of communications between Perez-Villanueva and Mujica, beginning in December 2017 and extending through January 2018, when he and Sacaria-Goday, along with Warren, were arrested in Ajo. According to Velasco’s testimony, the messages showed that when the young migrants entered the U.S. on January 14, Perez-Villanueva texted Mujica, “We’re here.” To which Mujica replied, “I’m on my way.” The government’s efforts to tie alleged illegal activity between Mujica and Warren appeared to begin after Warren was taken into custody. Four months after Warren was indicted, Jarrett L. Lenker, a supervisory Border Patrol agent in the Tucson sector intelligence unit, submitted a search warrant affidavit for Warren’s iPhone, first uncovered by the Arizona Daily Star and obtained by The Intercept. Mujica was a central figure in Lenker’s affidavit. The Border Patrol agent described “a total of 16 phone calls or WhatsApp messages” exchanged between Perez-Villanueva and Mujica in the month before his arrest. Lenker’s affidavit also revealed that, through subpoenas, law enforcement identified two phone numbers “associated with Warren’s Verizon account” following his arrest: one belonging to Warren and the other belonging to his partner. In his testimony Monday, Velasco said that Mujica was a contact in Warren’s phone, and that the two had communications up through January 11, six days before his arrest. Warren also sent Mujica’s contact information to another person in his phone in the summer of 2017, Velasco testified. Following Velasco’s testimony, the prosecution called Border Patrol agent Brendan Burns, one of the Disrupt unit members principally involved in Warren’s arrest, to the witness stand. Burns described an incident a week after Warren’s arrest, in which Mujica was pulled over at a Border Patrol checkpoint outside Ajo. He drove to the scene and observed that Mujica’s van was the same vehicle featured in a selfie Perez-Villanueva and Sacaria-Goday took after they made it to the U.S. Inside the van were a number of items associated with illegal border crossings, Burns testified, including water jugs and foreign identification cards. The same incident was also described in Lenker’s affidavit, which noted that the ID cards belonged to individuals who had been removed from the U.S. Lenker also recounted an incident the following month, in which Mujica was again stopped at the same Border Patrol checkpoint and his passenger was arrested for being in the country illegally. Burns acknowledged having seen the photos of Perez-Villanueva and Sacaria-Goday in Mujica’s vehicle prior to his encounter with Mujica, and his knowledge that the vehicle belonged to Mujica. He testified that he did not, however, ask Mujica about the two young migrants, nor their alleged conspiracy with Scott Warren, nor did he place him under arrest.

“The Barn,” a humanitarian aid shelter in Ajo, Ariz. Photo: Laura Saunders for The Intercept

In opening statements last week, defense attorney Greg Kuykendall acknowledged that Warren had been in contact with Mujica days before his arrest, and that was because Mujica had information about a dead body outside Ajo. The remains of roughly 3,000 people have been recovered in the Arizona desert since 2000, the grim consequence of a government policy that deliberately funnels migrants into the most lethal areas of the U.S.-Mexico border. Since 2014, Warren has brought together a network of humanitarian groups working to confront the loss of life in the state’s deadliest region, the so-called west desert. Those efforts have yielded a historic increase in the number of bodies and human remains accounted for in the area. On cross examination Monday, Kuykendall zeroed in on the evidence Velasco’s examination of Warren’s phone had uncovered. The defense attorney first established, with Velasco’s admission, that there were no communications recorded between Perez-Villanueva and Warren (Sacaria-Goday tossed his phone while the pair were in the desert). He then focused on Warren’s communications with Mujica. “Are you aware that Scott and Irineo are involved in humanitarian aid efforts?” Kuykendall asked. “I think I might’ve heard something,” Velasco replied. “But I’m not exactly sure.” (Warren’s humanitarian aid work was noted in both internal Border Patrol reports and news accounts before and after his arrest — he and Mujica were featured in a Pulitzer Prize-winning newspaper series in 2017 detailing their efforts to find dead and lost migrants in the desert.) Velasco admitted that he had no idea what Warren and Mujica discussed the week before Warren’s arrest, nor had he taken note of what Warren had Googled as soon as the pair got off the phone. Kuykendall informed the jury that those searches included information on backcountry areas south of Ajo and a news report on a humanitarian group conducting search and rescue operations in the region. After the migrants arrived at the Barn, he said, Warren looked up the English translation of a Spanish word for scratches, and shortly after that called Dr. Norma Price, a physician who has long provided medical advice to No More Deaths volunteers. Kuykendall questioned Velasco about his testimony regarding Warren’s communications with a woman named “Susannah.” Velasco admitted that he did not know who Susannah was and that he “saw nothing that directly suggested” she and Warren were communicating about criminal activity. Instead, he testified, they were messaging one another about “providing water in different areas.” Moving along, Kuykendall asked if Velasco was aware that Perez-Villanueva worked for Mujica while staying at his shelter in Mexico — a potential explanation for their repeated communications in the winter of 2017. Velasco appeared uncertain, and acknowledged that from January 10 to the afternoon of January 14, when the migrants arrived in Ajo, there were no communications between Perez-Villanueva and Mujica. “When he was crossing I didn’t come up with any messages,” Velasco testified. In opening arguments last week, Kuykendall explained how, in the days leading up to his arrest, Warren spent his time training new humanitarian volunteers, assisting sheriff’s deputies in the search for a body, and performing his duties as a new instructor at Tohono O’odham Community College, a school for residents of the Native American reservation outside Ajo. In early January 2018, five new No More Deaths volunteers had arrived in Ajo. As the local expert, it was up to Warren to show them the ropes and familiarize them with the organization’s protocols — protocols, Kuykendall said, that are intended to ensure the group’s work is “effective, responsible, and legal.” On Thursday, January 11, Warren was at home when Mujica called to inform him about the human remains he had heard about, Kuykendall said, noting that Warren had the experience and know-how to organize a grid search in the area. Efforts to coordinate a search were the extent of communications between Warren and Mujica, the defense attorney said. The following day, Warren took the new volunteers to a migrant shelter in Mexico, where they distributed “harm reduction” kits, consisting of chlorine to purify water, ointment for blisters, combs for removing cholla cactus spines, and lists of emergency numbers, including 911. “No More Deaths’ role is to reduce the harm,” Kuykendall told the jury, not to encourage people to cross a desert that has claimed thousands of lives. Warren spent much of the following weekend at home with the flu, Kuykendall said, coordinating rescue operations by phone and working to link up Pima County sheriff’s deputies with No More Deaths volunteers in the field. Warren’s responsibilities involved preparing new volunteers, operationally and emotionally, for the possibility of finding a dead body in the desert. On the night of Sunday, January 14, they also included making dinner for the new recruits at the Barn. Warren returned to the building with groceries that afternoon to find two young men — Perez-Villanueva and Sacaria-Goday — already inside. “Scott’s spooked,” Kuykendall said of Warren’s reaction. In the depositions played for the jury Monday, Perez-Villanueva and Sacaria-Goday described a harrowing journey through the desert that involved being chased by law enforcement and losing many of their supplies. Perez-Villanueva described fleeing problems in El Salvador and said that he had no intention to enter the U.S. until those problems cropped up in Mexico. The pair had crossed in a group of five but were quickly on their own, their companions slowed down by thorns in their feet. “Between the two of us, we made a good team,” Perez-Villanueva said. “We supported each other mutually.” The young men testified to crossing the desert and tossing their food and backpacks when they were chased by immigration agents. They eventually made it to a gas station outside Ajo, where “a gringo” drove them to second gas station in town. Neither of the migrants identified the man who then drove to the Barn, though Perez-Villanueva testified that the man told them not to describe his role in delivering them there, and that he honored that request. The pair let themselves in through an unlocked door. Warren arrived approximately 40 minutes later. “They tell him that they’re hungry,” Kuykendall told the jury. “They tell him that they’re thirsty. They tell him that they’re tired.” Warren grabbed a form No More Deaths uses to catalog medical evaluations of migrants encountered in the field, the defense attorney said. Warren, a certified wilderness first responder, found that Perez-Villanueva had blisters on his feet, a persistent cough, and signs of dehydration. Sacaria-Goday’s conditions were much the same, though he was also suffering from chest pain. In keeping with No More Deaths’ protocol, Warren called a nurse before starting dinner for the volunteers that were set to arrive — as well as their two new guests. “He gives food to hungry men,” Kuykendall told the jury. “They share a meal with the volunteers.” By phone, Dr. Price advised the two young migrants to stay off their feet for a couple days, to stay hydrated, and asked the volunteers to keep them under observation, Kuykendall told the jury. Warren came and went in the days that followed, as did other No More Deaths volunteers. “He hardly spent time there,” Sacaria-Goday testified. “I hardly spoke with him,” Perez-Villanueva said.