'These six years have been marked by alleged police and judicial incompetence and failures, which resulted in the families of the victims being denied justice,' Amnesty International said.

Amnesty International will be present in the courthouse in Belém to monitor the legal proceedings in the trial of the three commanding officers as an independent international observer. Edgardo Carvalho, a respected Uruguyan jurist, will be Amnesty International's delegate at the trial.

'The failures of the previous trial have raised international concern at the ability of the Pará justice system to provide the standards of justice required to ensure that those responsible for these crimes are held to account,' stressed Amnesty International.

Background

A previous trial for the 1996 killings of 19 landless activists took place in April 1999. Although all the high ranking police officers tried at that time were acquitted, this ruling was subsequently overturned following complaints of legal inconsistencies.

The 19 activists, many of whom were leaders of the Landless Rural Workers Movement (MST), were allegedly killed by members of the military police during a protest march. Autopsies revealed that some had been killed in execution-style shootings. Others had been hacked to death with their own farm tools. Some 100 policemen face charges for these killings.