Fourteen months after they arrived to investigate the disappearance of 43 college students, a panel of international experts is leaving Mexico, their case unsolved. Appearing at a press conference in Mexico City on Sunday, members of the independent panel, appointed by the Inter-American Commission for Human Rights, described a case tainted by government torture and deep prosecutorial mishandling.

Of more than 120 suspects arrested in connection with the students’ disappearance, 17 showed signs of torture, the panel reported. Of those allegedly tortured, five were key to the government’s account of the students’ fate, the experts said. The case has been riddled with media reports of suspects tortured into making confessions, and the words of Patricio Reyes Landa, whose testimony was made public in the report, offers a jarring description of the alleged abuse. Landa, a central suspect in the crimes whose confession was aired in nationally televised press conferences, said the description of his capture was a “lie.”

“They went into the house, beating and kicking,” Landa said. “They hauled me aboard a vehicle, they blindfolded me, tied my feet and hands, they began beating me again and gave me electric shocks, they put a rag over my nose and poured water on it. They gave me shocks on the inside of my mouth and my testicles. They put a bag over my face so I couldn’t breathe. It went on for hours.”

While the allegations of torture could thwart potential prosecutions in the case, they do little to explain what happened to the students. For that, the panel would need access to officials and evidence that it did not receive. The lack of access, the panel indicated, did not appear to be accidental. “The investigation had difficulties that are not attributable exclusively to the simple complexity of a case of this magnitude,” the report said.

From the outset, the Mexican government’s account of what happened on the night of September 26, 2014, has been the subject of withering criticism. According to the official story — once described by Mexico’s former attorney general as “the historical truth” — the students were intercepted by municipal police while attempting to commandeer buses in the city of Iguala, some three hours south of Mexico City. The students were then handed over to a local drug gang who drove them to a garbage pit where they were murdered and incinerated in a massive, makeshift funeral pyre, the government has contended.

As the initial details of the violence trickled out, the nation recoiled in horror. The students came from deeply impoverished backgrounds. Their school — officially known as Escuela Normal Rural Raúl Isidro Burgos but better known as Ayotzinapa — is a training college for aspiring teachers. The vast majority of the students attacked that night were freshmen who had little idea what they were getting into when they left campus. Not only were scores of unarmed students disappeared, but six people, a mix of students and bystanders, were killed in the process of their capture. One of the student victims was found beaten and bruised in the street; his assailants cut his face off. Within weeks, anger over the crimes led to fiery protests that soon spread across the country.

In May, The Intercept published a series of articles about the students’ disappearance, based on six months of investigation and more than two dozen interviews, including conversations with survivors of the attacks, as well as a review of state and federal records, including communications reports by Mexican security forces and sealed statements from municipal police officers and alleged gang members who were detained in the wake of the crimes. The Intercept found major inconsistencies in the government’s story. Rather than a local crime committed by municipal officials and their gangster accomplices, ample evidence, including the government’s own records, pointed to a wider circle of responsibility and a clear-cut case of enforced disappearance — a crime against humanity under international law.

Speaking at the press conference in Mexico City this weekend, members of the panel reiterated, for the second time, the core conclusions of investigative articles published by The Intercept and other news outlets. In a rebuke of the government’s narrative of a limited, local operation, the panel reported that it had uncovered new evidence of wider federal police involvement in the night’s events. Regarding the assertion that the students were collectively incinerated, the experts repeated their long-held position that this was not the case. “[The panel] has not a single piece of evidence to change its conclusion that the 43 students were not incinerated,” Francisco Cox, a Chilean member of the team, said.

The panel’s first report was published in September of last year. The 560-page document meticulously deconstructed the government’s account and presented the events that night for what they were: a hyper-violent, coordinated, multi-pronged ambush of unarmed civilians at multiple locations resulting in at least six people dead, 40 injured, and 43 disappeared, carried out with full knowledge, if not outright participation, of security forces at all levels, including federal police and the military.

The experts had come to Mexico at the government’s invitation. With the authority to conduct an independent investigation and promises that the state would aid in making the necessary evidence and witnesses available, their presence offered a glimmer of hope that the most shocking crime in recent Mexican history might actually get solved. That hope soon crumbled though.

Following their first report, the experts’ relationship to the government turned cold, according to an account members of the panel provided to the New York Times. The government refused to make key interviews possible, including interviews with members of the military potentially present on the night of the students’ disappearance. Meanwhile, the experts themselves were attacked in media outlets close to the state, and an individual who appointed them became the target of a dubious criminal inquiry. Despite a sense that their job was not done, the experts were not offered an extension of their mandate. They are expected to leave Mexico in the coming days.

The search for the students has turned up scores of clandestine graves in the southern state of Guerrero, where the attack took place. To date, the remains of just one of the young men, 21-year-old Alexander Mora Venancio, has been positively identified. Exactly where his remains were found is deeply contested. The Intercept met Mora’s father, Ezequiel, on a rainy night on the Ayotzinapa campus. He was taking shelter beneath an awning. Violence, intimidation, disappearances — that’s how the government does business, Ezequiel explained. “It is their policy,” he said. “It is a narco-government. It is not a government that is for its people.”

Mexicans have a phrase to describe those moments in which things boil over: The drop that spilled the glass. The phrase was heard again and again when the outrage over the students’ disappearance was at its peak. The 43 young men, the pain that was evident on their parents’ faces as they marched through the streets, the government’s obscenely flawed investigation — all came together as a visceral representation of what so many Mexicans have suffered in recent years. When it spilled over into massive demonstrations across the country, there was hope that for once things might turn out differently.

According to government estimates that are regarded as conservative, at least 25,000 Mexicans have disappeared over the last decade. In a country where impunity is rampant, those cases stand a slim chance of ever being solved. With the independent investigators’ inquiry into the disappearance of 43 students coming to a close, the likelihood that they will be removed from that grim tally slips further away.