Inquiry Challenges Mexico’s Account of How 43 Students Vanished

MEXICO CITY — Since November 2014, the Mexican authorities, eager to close a dark chapter in the nation’s history, have insisted that 43 students from Ayotzinapa who disappeared two months earlier in the city of Iguala were killed by a drug gang that incinerated their bodies in a garbage dump and disposed of the ashes in a river.

But on Sunday, in the latest blow to the integrity of the government’s case, an international panel of experts who began examining the disappearances a year ago asserted that five suspects whose testimony underpinned the government’s conclusions gave confessions “under torture or cruel, inhumane or degrading treatment.” Forced confessions are not admissible in Mexican courts.

The findings not only undermined the government’s case but also further eroded the credibility of the nation’s criminal justice system. The system has been widely criticized for its handling of a matter that has come to represent the failures and corruption of the Mexican state.

“The Ayotzinapa case has put the country at a crossroads, from which it has yet to emerge, and for that it needs a strengthening of the rule of law and of the defense, the guarantee and respect for human rights,” Alejandro Valencia, a Colombian lawyer and a member of the five-person panel, said at a news conference here on Sunday.

The government’s response to the students’ disappearance in September 2014 has become a referendum on the administration of President Enrique Peña Nieto, who took office in 2012 promising to reduce violence. The case set off months of street protests and demands that the government solve the mystery and end chronic corruption.

The panel of experts, who were invited by the Mexican government to examine the case, revealed its findings in the news conference and in a voluminous report — its second and last. The mandate of the group, which was appointed by the Inter-American Commission on Human Rights and is made up of Latin American lawyers and human rights activists, expires next week, and the Mexican authorities have said they will not extend it.

Beginning with their first report, in September, the experts have systematically dismantled the government’s conclusions, questioning the authorities’ ability or commitment to thoroughly investigate the disappearances and raising doubts about the integrity of the judicial system.

The panel “has not a single piece of evidence to change its conclusion that the 43 students were not incinerated” in the dump, Francisco Cox, a Chilean lawyer and one of the experts, said at the news conference.

The government announced in January 2015 that it had solved the mystery after what Jesús Murillo Karam, then the attorney general, called an “exhaustive, serious” inquiry.

Mr. Murillo said the students, who attended a teachers college in Ayotzinapa in the Pacific state of Guerrero, had traveled to Iguala to commandeer buses for transportation to a protest in Mexico City. According to the government’s version of events, Iguala’s mayor ordered the police to detain the students.

The government’s account, which relied on the testimony of several members of a drug gang, said the police had then turned the students over to the gang, which killed them, incinerated their bodies in a dump near Cocula and threw the remains in a river.

In recent months, a team of experts on torture, working with the international investigative panel, examined evidence gathered by the Mexican authorities. Using United Nations guidelines for the documentation of torture, the technicians determined that 17 of the government’s suspects had been tortured, including five gang members who claimed to have been involved in the killing and burning of the students.

The findings supported testimony by some of the suspects that they had been tortured while in the custody of government security forces.

The experts also raised urgent questions about the way the Mexican authorities had gathered and handled evidence in the case, especially a bone fragment found in October 2014 that was linked to one of the missing students.

“This is a serious problem that needs to be investigated,” said Carlos Beristain, a Spanish doctor and a panel member.

Among their other findings in their 608-page report, the experts said they had uncovered new evidence that pointed to a greater role by federal security forces in the events of Sept. 26-27, 2014, despite the Mexican authorities’ insistence that the crimes committed that night were local in nature.

The experts also lamented the lack of investigation into the possible culpability of all but low-level officials.

“You must look for not only the direct authors of an action but also for those who led, supported or ignored the signs of human rights violations,” the panel wrote.

The panel also raised questions about why the government’s investigation had failed to analyze phone records from that night, which might have shed light on where the students had been taken.

The experts reiterated their longstanding criticism that the Mexican government had blocked their access to crucial witnesses, including all military officials, and did not allow them to reinterview scores of witnesses. Requests for certain documents and testimonies were ignored or rebuffed, they said.

Eber Omar Betanzos, the deputy attorney general for human rights, responded to the experts’ report by rebutting many of their specific arguments and said the torture allegations were being investigated. The government had given the experts “full access to the information needed to develop their work” and had answered 85 percent of their 941 requests, he said, adding that the remaining 15 percent were close to completion.

The experts also criticized sclerotic bureaucracy. They held up the matter of Julio César Mondragón, one of the students who had gone to Iguala. He had become separated from his friends during the chaos of the night, and his body turned up the next morning in Iguala. He had been so brutally tortured that he was not immediately identifiable.

The first autopsy on the body was incomplete, the experts said, so they requested a second one. Even though they pushed the request, the Mexican authorities took three months to approve a second autopsy. In their latest report, the experts likened the agonizing wait by the student’s family to “a new victimization” that arises “when bureaucracy or formal aspects are more important than the victims.”