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26 Apr 2017 | Commentary

One Year Since the Group of Experts Left Mexico: The Ayotzinapa Case is Still Unresolved and Disappearances Remain High


In September 2014, students from a rural college in Ayotzinapa, Guerrero commandeered commercial passenger buses outside the city of Iguala, Guerrero and later commandeered three more within the city. On their way out of the city, the students were attacked by police officers working in collusion with the criminal organization Guerreros Unidos. During a series of attacks in various locations, 6 people were killed, dozens were injured, and 43 students were forcibly disappeared. Following the incident, the Mexican government signed an agreement with the Inter-American Commission on Human Rights (IACHR) and the legal representatives of the victims and their families from the Miguel Agustín Pro Juárez Human Rights Center and the Tlachinollan Human Rights Center to allow an international team of criminal justice, human rights, and victims rights experts to provide technical assistance to Mexican authorities in the investigation of the case. The Interdisciplinary Group of Independent Experts was formed and worked on the investigation from March 2015 until April 2016. One year has passed since the Group of Experts concluded their work on the Ayotzinapa case and much work remains for the Mexican government to resolve the case and find the students.

The end of April marks one year since an independent team of investigators, called the Interdisciplinary Group of Independent Experts, concluded their work on the case of the 43 disappeared students from Ayotzinapa and left Mexico. In the year since the Group of Experts left, limited progress has been made in the investigation and the Mexican government still maintains its original theory about what happened to the students—a theory that the Experts disproved based on scientific evidence.

The Group of Experts was established through an agreement between the Mexican government, the Inter-American Commission on Human Rights (IACHR), and the legal representatives of the victims and their families from the Miguel Agustín Pro Juárez Human Rights Center and the Tlachinollan Human Rights Center to allow an international team of criminal justice, human rights, and victims rights experts to provide technical assistance to Mexican authorities in the investigation of the case.

On April 20 and 21, members of the IACHR visited Mexico to follow up on the Group of Experts’ work and the recommendations it left for the Mexican government to continue with the investigation. After the visit, the IACHR expressed “concern about the slow pace in coming to conclusions, both in the search activities and in the effective clarification of the various lines of investigation indicated by the Inter-Disciplinary Group.”

The Group of Experts’ work was essential in disproving the so-called “historic truth” that the Mexican government tried to impose on the investigation—that the students had been detained, killed, and their bodies burned and thrown into a nearby river—and to counteract the Mexican government’s rush to close the case. The Experts helped move the investigation forward, uncovering key evidence and highlighting many credible lines of investigation to explore. They concluded that a possible motive for the large-scale attacks against the students could be that the students unknowingly took a bus containing heroin, and they recommended pursuing this line of investigation.

The Experts also revealed strong evidence that implicated several Mexican authorities in the obstruction of justice. During their time in Mexico, the Experts published two comprehensive reports about their findings and recommendations for how to move forward in the investigation; the final report was presented on April 24, 2016.

Following the Experts’ departure, in July 2016, the IACHR established a Follow-Up Mechanism for the Ayotzinapa investigation under a new agreement with the Mexican government, the students’ families, and their representatives. The Mechanism’s work plan outlines its objectives, timeline, and activities, including four official visits of the IACHR to Mexico.

An Emblematic Case that the Government must Resolve

The Mexican government has called the Ayotzinapa case “the most exhaustive investigation in the history of Mexico”—yet the case remains unresolved and the investigation is riddled with irregularities, including mishandled and lost evidence and allegations of the use of torture to obtain testimony. The Mexican government has dedicated significant resources to the Ayotzinapa investigation, but authorities have yet to secure any criminal convictions or find the students. This lack of results after so much time raises questions about the Mexican government’s capacity and political will to investigate and sanction those responsible, as well as its political will to address the broader problem of disappearances in the country.

One year after the Group of Experts left and two and a half years after the students disappeared, here are some of the issues the government still must resolve for the families and victims.

The Government Refuses to Abandon its Disproven “Historic Truth”

The Mexican government refuses to abandon its official theory of the case, despite the findings of the Group of Experts. In a March 17, 2017 hearing before the IACHR, the Mexican government stated that its only theory about the case is that the students were killed and burned at a trash dump by members of an organized criminal group, despite the fact that this theory was disproven by the Group of Experts and several scientific studies. The IACHR considered the Mexican government’s defense of its “historic truth” to be very grave and reiterated that the IACHR has already discarded this theory of the case. During the visit to Mexico, the IACHR expressed concern about public statements made by high-level Mexican officials validating this theory. Following the hearing, the Mexican government issued a statement saying it will exhaust “all possible lines of investigation” and heed the Group of Experts’ recommendations. The government must now transform those statements into concrete actions.

Obstacles in the Internal Investigation

One of the Group of Experts’ primary recommendations was to conduct an internal investigation into the possible obstruction of justice by Mexican authorities. For example, in a video uncovered by the Group of Experts, the then-head of the Criminal Investigation Agency (Agencia de Investigaciones Criminales, AIC), Tomás Zerón, is seen at the San Juan River, where plastic bags containing burned remains were discovered and where a fragment of bone belonging to one of the students was identified (the only positive identification made in the case). Official government records show that the bags were discovered on October 29, 2014. However, this video shows Zerón on October 28 at the river with plastic bags and one of the key defendants who was removed from custody—a day before authorities officially announced finding this evidence.

Through August 2016, César Chávez, the then-Inspector General within the federal Attorney General’s Office (Procuraduría General de la República, PGR), conducted an investigation into the actions of officials in the case. Before his results were officially presented and shared with students’ families and lawyers, Chávez abruptly stepped down in September 2016. The Mexican media and The New York Times obtained a copy of Chávez’s investigation which found 13 serious irregularities in the actions carried out by PGR personnel, including Tomás Zerón. Chávez had even recommended further investigations be carried out to determine whether certain officials’ conduct could be cause for criminal sanctions. Far from being sanctioned, Tomas Zerón left the PGR and was appointed as Technical Secretary of the National Security Council (Consejo Nacional de Seguridad).

Chávez was replaced by a new Inspector General, Adriana Campos López, who officially concluded the internal investigation and submitted the final report in December 2016. Campos’ report does not question the government’s original version of the case and it only cites 7 minor infractions made by authorities that could lead to administrative sanctions.

Key Evidence was Withheld from the Group of Experts

In November 2016, it was revealed that the current head of Mexico’s Criminal Investigation Agency, Omar García Harfuch, may have links to the Guerreros Unidos criminal organization. García previously worked with the Federal Police in Guerrero as the State Coordinator for Regional Security; he moved to the Criminal Investigation Agency after Tomás Zerón left in September 2016. The Mexican newspaper Proceso obtained a copy of a legal ruling against Sidronio Casarrubias Salgado, a Guerreros Unidos leader who was detained in October 2014. The ruling describes the evidence in the case, including a small notebook that listed contact numbers for government officials in Guerrero, including García Harfuch. This information was not shared with the Group of Experts during their time in Mexico.

This notebook also mentioned the alias name “El Uruguayo.” The lawyers of the victims looked into the alias and discovered that “El Uruguayo” is Gonzalo Martín Souza Neves, a suspected leader of Guerreros Unidos. Souza was detained in July 2014—a few months prior to the students’ disappearance—during a military-led operation where he was discovered to be in possession of large sums of U.S. cash and ilicit drugs, which he allegedly had plans to transport using hidden compartments in vehicles, primarily commercial passenger buses.

It is now clear that the Mexican government had prior evidence of the Guerrero Unidos’ practice of using buses to traffic drugs to the United States. This information was deliberately withheld from the Group of Experts, which on multiple occasions requested information about prior cases that involve the use of buses to traffic drugs.

This evidence is key because, as previously mentioned, the Group of Experts concluded that a possible motive for authorities’ massive and sustained attack against the students on the buses was that the students’ unintentionally intervened in a Guerreros Unidos’ operation that used passenger buses to traffic heroin to the United States, specifically to Chicago, Illinois. The U.S. Department of Justice (DOJ) is currently investigating a case in Chicago involving the Guerreros Unidos and this modus operandi. The Mexican government did not investigate this hypothesis and took several months to request information from the DOJ about its investigation into Guerreros Unidos trafficking operations to Chicago.  

Limited Progress in the Investigation and Search for the Students

In recent months, Mexican authorities have made some progress in determining the involvement of different authorities in the attacks against the students. By tracking phone use and signals, authorities confirmed the participation of the Huitzuco police, a neighboring town to Iguala, in the attacks. Authorities are still analyzing the phone data of the disappeared students and some of the detainees. Phone companies have turned over thousands of sheets of data from over a thousand phone numbers under investigation.

Additionally, Mexican authorities have used LIDAR technology to identify potential clandestine graves where the disappeared students could be. In December 2016 and February 2017, new searches were carried out in areas around Iguala using information derived from the LIDAR technology. It is important to continue these efforts but it is also crucial that Mexican authorities more effectively organize their registry of clandestine graves in order to avoid searching in graves that have already been uncovered by different authorities.

Pending Steps

Carry out serious efforts to locate the students and sanction those responsible for their enforced disappearance: Mexican authorities must continue to search for the students, including by using LIDAR technology. During its visit, the IACHR also recommended that the Mexican government create “a database of graves that can be replicated in all states.” Mexican investigators must also finish their analysis of phone signals and usage, both to know what it reveals about the students’ whereabouts and to determine which authorities participated in the attacks against the students. Above all, the Mexican government must respect the agreements it has made with the victims’ families to search for the students.

Sanction officials who acted irregularly or illegally during the investigation: Given the significant differences in the final internal report submitted by the current Inspector General and the report by the former Inspector General Chávez, Mexican authorities should carry out a new internal investigation into the authorities that may have obstructed justice. The government should also investigate officials responsible for concealing key evidence from the Group of Experts about prior cases involving drug trafficking to the United States and criminal groups in Iguala, like the Guerreros Unidos. Authorities should also investigate the possible links between Mexican officials and organized criminal groups.

Fully investigate the hypothesis connected to drug trafficking: Since additional evidence regarding the use of buses for transnational drug trafficking has been discovered, Mexican authorities should commit to thoroughly investigating the possibility that the motive for the attack against the students was their unintended intervention in a drug trafficking operation. The IACHR believes it is urgent to fully explore this line of investigation.

Continue investigating the participation of different authorities in the attacks on the students: Although investigators have confirmed the participation of Huitzuco municipal police officers in the attacks against the students, there has been no progress investigating two Federal Police agents who were present at one of the scenes where some of the students disappeared. These agents have been identified by the Group of Experts and Mexico’s National Human Rights Commission (Comisión Nacional de los Derechos Humanos, CNDH) for allegedly participating in covering up events in the case. Authorities have also not investigated other state and federal security forces that were present at different scenes the night the students disappeared.

Resolve the serious problem with disappearances in Mexico: The Mexican government has not adopted sufficient measures to ensure a prompt and coordinated search when people are reported as missing. Nor have they undertaken sufficient efforts to facilitate the identification of remains and the location of mass grave sites. The case of the 43 students is just one of more than 30,000 disappearances officially registered in Mexico. The Mexican government’s primary obligation is to prevent people in Mexico from disappearing at the hands of criminal groups or public officials, but when it happens, the government must immediately search for the person and investigate those responsible.

In recent months in Mexico, clandestine graves and unidentified human remains have been discovered in official public grave sites, which highlights the need to improve forensic capacities in Mexico. In a special report on disappearances, the National Human Rights Commission reported that between 2007 and 2016 in Mexico, 855 clandestine graves had been officially located and contained 1,548 bodies, of which nearly half have been identified. In March 2017, authorities in Veracruz revealed that 125 mass graves containing 14,000 skeletal remains had been discovered in the state since August 2016. In the efforts to search Ayotzinapa students, investigators have uncovered countless mass graves in Guerrero.

As part of its work on the Ayotzinapa case, the Group of Experts worked to address the broader issue of disappearances in Mexico. The Group of Experts recommended that the Mexican government adopt an adequate legal framework to investigate disappearance cases. Mexico’s Congress took a positive step forward in July 2015 when it amended the Constitution to give legislators the power to pass legislation applicable throughout the country on the subject of disappearances. The deadline for issuing the general law on disappearances in Mexico expired on January 6, 2016. However, the law remains stuck in the Mexican Senate. The Executive branch recently proposed changes to the current draft bill that represent a step backward from the proposals submitted by families of disappeared persons, civil society organizations, and experts. Relatives of disappeared persons have given the Mexican government a vote of confidence to issue a law that will once and for all end disappearances in Mexico. It is up to the Mexican government to honor its word. Mexican lawmakers should prioritize passing a comprehensive law that takes into account the demands of victims and civil society groups.