Brazil's Truth Commission will investigate only human rights abuses committed by the country's former dictatorship, not any crimes committed by opponents of the 1964-1985 regime.
The commission said Tuesday on its website that it has been told to only look at the torture, murder and forced disappearances carried out by government agents of people opposed to the dictatorship.
It said it did not have the authority to investigate the acts of individuals that were not public agents.
Retired military officers criticized the announcement, saying the panel must also look into violations committed by leftist guerrillas who opposed the regime.
Retired admiral Ricardo Antonio da Veiga Cabral said by telephone that the commission's decision will result in an "unfinished, one-side investigation in which only half the truth will be known."
"Crimes were committed by both sides, so both sides must be investigated," he said.
Retired officers often express the opinion of the armed forces since military personnel are prohibited by law from doing so publicly.