A federal judge on Friday blocked prosecutors' efforts to hold the first trial of a military man for abuses committed during the nation's dictatorship.
Judge Joao Matos ruled that kidnapping charges filed earlier this week against retired army Col. Sebastiao de Moura would go against Brazil's 1979 amnesty law. The amnesty bars prosecutions for politically motivated crimes that were committed during the 1964-85 military regime.
Prosecutors said in an emailed statement that they would appeal. Their decision to pursue the case was applauded this week by the United Nations and humans rights groups.
The judge's decision comes amid a debate in Brazil about the creation of a truth commission to investigate crimes committed under the dictatorship.
President Dilma Rousseff, a former leftist guerrilla, was imprisoned for more than three years during the junta and brutally tortured. In November, she signed into law a bill that established the truth commission, but she has yet to appoint its seven members, who will have two years to complete a report.
The commission still faces resistance from conservative corners in Latin America's largest nation, and more than 400 retired military personnel have signed documents sharply criticizing the measure.
It will have subpoena power, can demand any document it wants from the government and can put witnesses under oath.
But its recommendations are unlikely to result in any prosecutions as long as the amnesty law remains intact. Unlike Argentina, Chile and Uruguay, which also had repressive military regimes, Brazil has never punished military officials accused of human rights abuses.
Earlier this week, prosecutors filed five kidnapping counts against Moura for abductions that they say were carried out during the repression of the leftist Araguaia guerrilla movement. The rural Communist group was crushed by government forces between 1972 and 1975, a period during which 62 of its members were "disappeared."
"To intend, after three decades, to evade the amnesty law, and to reopen a discussion about crimes carried out during the military dictatorship is wrong and is devoid of legal backing," the judge wrote in his ruling.
Murilo Abreu, a spokesman for the federal prosecutors office in Para state, where the charges were filed, said prosecutors were not surprised Matos blocked their efforts "because a lot of people feel it would go against the amnesty law."
Prosecutors argue the kidnappings and the hiding of bodies so the victims were never found are "permanent crimes." Since such crimes continue to the present, they fall outside the 1961-79 period covered by the amnesty law, federal prosecutor Tiago Rabelo said earlier this week.
Rabelo said there is material proof, such as reports from the time and historical records, that show Moura participated in kidnappings. There are also numerous witnesses, he said.
"They all point to (Moura) as the author of the crimes," Rabelo said.
In 2010, the Inter-American Court of Human Rights held the Brazilian government responsible for the forced disappearances of the 62 alleged members of the Araguaia guerrilla movement.
"We're willing to carry out the determination of the Inter-American Court of Human Rights that made clear Brazil's obligation to find the truth ... to give closure to the families that even today have none," said Ubiratan Cazetta, one of the federal prosecutors who brought the charges.
In Geneva on Friday, the United Nations' human rights office said the prosecutors' decision to bring charges was "a long-awaited development towards accountability" for its military dictatorship between 1964 and 1985.
Spokesman Rupert Colville called the effort to bring Moura to trial "a first and crucial step in fighting the impunity" of Brazil's military era, adding that "under international law there should never be an amnesty for serious international crimes."
Associated Press writer Stan Lehman contributed to this report.