The long-awaited trial into one of Central America’s most notorious murders has been thrown into disarray after the judges were formally accused of abuse of authority and a cover-up.

The opening of the trial of eight men charged over the murder of Honduran indigenous leader Berta Cáceres was postponed after lawyers representing her family requested that the three judges be recused and replaced.

Cáceres was shot dead in her home on 2 March 2016 after a long battle opposing the internationally financed hydroelectric dam on the Gualcarque river, which the Lenca people consider sacred.

She was an internationally renowned grassroots defender of indigenous and land rights, who was awarded the prestigious Goldman prize in 2015 for leading the campaign to stop construction of the Agua Zarca 21 MW dam.

Cáceres’ murder triggered international condemnation, and demands for justice in a country where impunity is rampant.

Today’s application argued that a series of decisions and omissions by the judges during pre-trial hearings violated due process and demonstrated bias against the victims.

The application alleges that the judges’ showed a disregard for the rule of law by refusing to sanction the public prosecutor’s office for ignoring court orders to share evidence with the family’s legal team.

In addition, five injunctions submitted last week must also be resolved by the appeals court. In one, the family’s lawyers contest the “arbitrary decision” by the judges to reject witnesses, experts and documentary evidence linking the murder to a wider criminal conspiracy.

Victor Fernandez, one of the lawyers representing Cáceres’ three daughters and mother, said: “We will not tolerate or stay silent about institutional abuses, no matter how routine and normalized these abuses are in the criminal justice system in Honduras, because that will guarantee impunity for the criminal structures responsible for the murder.”

Cáceres, the coordinator of the Civic Council of Popular and Indigenous Organizations of Honduras (Copinh), was subjected to surveillance, harassment, false criminal charges and multiple death threats before she was killed.

The eight defendants are also charged with the attempted murder of Gustavo Castro, a Mexican environmentalist who was injured in the gun attack but survived by pretending to be dead. Five were arrested in May 2016. The law requires cases to be resolved within two and a half years after detention. Failing to do so could provide grounds for appeal.

“We want justice but we want a fair trial, which respects due process for us the victims and the accused,” said Bertita Zuniga Cáceres, the murdered leader’s daughter and current Copinh coordinator.

In a bizarre start to proceedings, the hearing was initially delayed as the judges decided to hear a petition from an unrelated drug trafficking case. Three hours later than scheduled, the jam-packed courtroom was informed that the trial was suspended until the appeal court decides whether the judges are competent to proceed or not. Under the law, the recusal ruling should be issued within 72 hours.