Mexico's botched investigation of 43 missing students leads chief investigator to resign

Tomás Zerón, the Mexican official who headed the investigation into the disappearance of 43 students nearly two years ago, has resigned, but parents of the students see it as an empty gesture since he's being rewarded with another high-level government job.

"Instead of punishing him they have given him a prize," said Hilda Hernández, mother of one of the students, at a press conference Thursday. "It doesn't change anything. We are going to continue taking to the streets to demand the return of our children alive, and to demand the truth."

The announcement of Zerón's resignation as chief of criminal investigations Wednesday was widely reported as an effort to defuse tension with the families as they prepare a protest to commemorate the crime's second anniversary on September 26. Its chances of success, however, were immediately reduced by a second announcement that Zerón will now take up a new job as a high-level presidential advisor on security matters.

The disappearance of the students nearly two years ago after they were attacked by police in league with a drug cartel in the southern city of Iguala, exploded President Enrique Peña Nieto's efforts to treat Mexico's security crisis as a secondary problem while he pushed through an ambitious pro-market reform agenda.

An initial wave of mass demonstrations faded after a few months, but public irritation over the case has continued to flare up periodically ever since, often triggered by reminders of the obvious inadequacies of the official investigation.

Many have never believed the probe's early conclusion that the students, from the famously radical Ayotzinapa teacher training college, were killed and then incinerated on a huge pyre in a garbage dump on the same night of their abduction.

Investigators based the story on the confessions of a handful of detainees they said led them to find plastic bags full of ash and a few bone fragments in a nearby river. Tests later matched one of the fragments to one of the missing students.

Since then, most of the key suspects have withdrawn their confessions with claims of torture. Fire experts have also argued that the pyre could never have been of the size and intensity required to reduce the bodies to mostly ash.

Zerón himself became a target of specific allegations of manipulating the probe following the release last April of a report from a special commission of foreign experts appointed to "support" the government's investigation.

The report highlighted videos showing Zerón walking beside the river with one of the confessed suspects, as well as images of plastic bags on the river bank similar to ones that would later be found in the water. It also underlined that the trip to the river was not recorded in the case file.

At the time the government, which had already politely asked the experts to leave, ignored the clamor for Zerón's resignation, as well as the fury of the relatives of the missing students.

The Ayotzinapa case, meanwhile, has refused to go away and remains a major thorn in Peña Nieto's side as he struggles to reverse approval ratings that had reached record lows even before his disastrous meeting with Donald Trump last month that prompted near-universal condemnation in Mexico for his failure to demand an apology for the candidate's offensive statements about Mexico and Mexicans.

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