Mexico's Supreme Court on Wednesday rejected a bid to release a Frenchwoman serving a 60-year sentence for kidnapping, but it opened a door to a retrial on the grounds her rights were violated before her conviction.
A five-judge panel discussed a motion to free Florence Cassez, arrested in 2005 by federal officers at a ranch near Mexico City with her ex-boyfriend, Israel Vallarta, who they accused of heading a kidnapping gang called the Zodiacs.
Three of the judges rejected immediately freeing the 37-year-old Cassez, whose case has caused a diplomatic dispute between Mexico and France. But a majority said infringements of her rights and police misconduct meant her case could need to be reheard or a new sentence passed.
"We need to establish that the responsible authority, without taking into account the specific factors corrupted by procedural infringement, re-evaluates the evidence," said Judge Jose Cossio, who voted against Cassez being granted her freedom.
In Paris, a spokesman for the French Foreign Ministry said France strongly regretted that Cassez would stay in prison. The case has been followed closely in France, where President Nicolas Sarkozy has pressed for her release.
Cassez, who is at a women's prison in southern Mexico City, has always maintained her innocence. In a prison book about her experiences, she wrote she traveled to Latin America to stay with her brother, and had a difficult relationship with Vallarta that led to her arrest.
When she was arrested in December 2005, police, instead of first taking her to a prosecutor or advising the French Consulate, forced Cassez to take part in a staged scene of officers freeing kidnap victims in a different location.
Cassez was portrayed as a kidnapper in the recreation, which was aired on national television as if it were a real event. Police have since admitted their wrongdoing.
A judge convicted Cassez in 2008 after a closed-door trial with no jury, typical of cases in Mexico.
The most powerful evidence used to convict Cassez was provided by three kidnapping victims, one of whom said she had threatened to cut off his finger.
The motion put forward by Judge Arturo Zaldivar argued that witness statements against Cassez were unreliable and contradictory, and that the rights infringements had denied her a fair trial.
Cassez's lawyer, Agustin Acosta, said that while she had not been freed, the court's move was a step forward.
"We would have liked the motion to have been approved, but we're establishing that there were violations. Four judges established that there were violations and a new trial is sure to annul the sentence," Acosta said.
An official for the court said that because at least three of the judges had ruled that Cassez's rights had been violated, the Supreme Court by law had to consider a new motion to resolve the case, which could result in a retrial.
The official said it could take months before a new motion was put forward. Procedural hurdles had to be negotiated before any retrial, and other options to settle the case could also be pursued, the official added, without giving details.
Cassez's case has sparked denunciations of Mexican justice both in France and from Mexican intellectuals.
Those calling for her release say her treatment means the case is no longer about whether the Frenchwoman is guilty - but whether Mexican justice functions properly.
Senior officials in President Felipe Calderon's administration have backed her conviction, and a poll published in a Mexican newspaper this week showed the vast majority of Mexicans wanted her to stay in prison.
Those opposing her release argue it would be an affront to the victims of kidnapping in Mexico, where many of the guilty go unpunished.
Elias Huerta, an anti-crime activist at the courthouse, said that even if Cassez were given a retrial, he was confident that the verdict would be the same. "The evidence of the victims is not going to change," he said.
Federal prosecutors have countered accusations that Cassez was not given a fair hearing by saying failings in procedure should not imperil the right of victims to justice.
Mexico suffers from one of the highest levels of kidnapping in the world, with almost 3,000 cases filed to authorities last year. Many more are believed to go unreported.