Brazilian President Dilma Rousseff has sworn in the seven members of a truth commission created to investigate human rights abuses committed during the nation's long military dictatorship.
"We are not moved by revenge, hate or a desire to rewrite history"
- Dilma Rousseff - Brazil President
The seven-member commission will examine the period from 1946 to 1988, but a military-era amnesty means there will be no trials.
Rousseff, a former leftist guerrilla who spent three years in prison during the dictatorship and was brutally tortured, was moved to tears as she ushered in the long-delayed commission, whose work begins years after neighbouring Latin American nations fully investigated the actions of dictatorial regimes.
"We are not moved by revenge, hate or a desire to rewrite history," said Rousseff said at the ceremony in Brasilia.
"The need to know the full truth is what moves us. Brazil deserves the truth, future generations deserve the truth and most importantly those who lost their friends and their families deserve to know the truth."
A study by the Brazilian government concluded last year that 475 people were killed or "disappeared" by agents of the military regime, which ruled Brazil from 1964 to 1985.
The commission, which will have two years to conclude its investigation, will not prosecute anyone because of a 1979 amnesty law that released civilians and the military from liability for politically motivated crimes committed during those years.
There has already been criticism from army officers and victims' relatives of the commission's remit.
Some commission members have said they will focus only on abuses committed by the armed forces. But retired military officers want it to also look into violations committed by leftist guerrillas who opposed the regime.
Retired officers often express the opinion of the armed forces since military personnel are prohibited by law from doing so publicly.
Commission members Rosa Cardoso and Paulo Sergio Pinheiro told the O Estado de S. Paulo newspaper that the commission's main purpose is to investigate abuses committed by government agents. Cardoso is the attorney who represented Rousseff when she was imprisoned by the military in the early 1970s.
But former officers say that is not fair.
Supporters of the truth commission argue that it will help Brazil to come to terms with its recent past.
The commission will reveal the abuses and the names of those who committed them.
Retired officers have announced that they are setting up a parallel commission to counter any accusations that emerge.