From 1964 to 1985, Brazil was ruled by a military dictatorship that tortured and murdered dissidents in the name of fending off communism. The generals who ran the country have long denied the use of such brutal tactics, but a newly unearthed CIA memo reveals that Brazil's top leaders knew and approved of a policy to execute people seen as threatening to the regime.

In the two decades after Brazil's military overthrew a democratically elected government in 1964, researchers say, the regime committed numerous atrocities. Interrogators utilized electric shocks on victims drilled nails into their hands and doused their extremities in alcohol before setting them on fire. Hundreds of people deemed a threat to the government died or went missing.

But whether the country's top leaders endorsed such behavior has been hard to pin down: Brazil’s military maintains that all classified documents from the dictatorship were destroyed. The CIA document offers a rare crumb of hard evidence.

The 1974 memo to then-Secretary of State Henry Kissinger describes a meeting between Brazilian President Ernesto Geisel and military intelligence leaders. According to the memo, Geisel was briefed on an existing policy of executing “subversives.” After reflecting on the policy for a weekend, he decided to maintain it.

“This document specifically shows that in fact, there was a chain of command when it came to repression, that it was not something happening in the basements of prisons that the leadership knew nothing about,” said Marcelo Ridenti, a sociology professor at the University of Campinas in São Paulo. “It reveals something that historians and even family members of political prisoners already knew, in some sense, but it offers proof to claims that had yet to be confirmed.”

The violence of the dictatorship still haunts Brazilian politics. The country's past three presidents were jailed or went into exile during military rule. In 2012, then-president Dilma Rousseff, a former political prisoner, launched a Truth Commission to investigate the generals' atrocities. The commission accused more than 300 people of grave human-rights abuses, but they never faced jail time thanks to an amnesty law they negotiated before relinquishing power.

In light of the explicit endorsement of the murders described in the CIA memo, many in Brazil are calling for a second look at the amnesty law and the return of the Truth Commission. Ivo Herzog, whose father was tortured and killed by the dictatorship, petitioned the Brazilian foreign ministry to request that the United States release more documents about the generals.

“The historic documents that narrate this terrible chapter in our country’s history, which the Brazilian government through the military has claimed have been destroyed, were preserved by another nation,” he said in an open letter. “A country needs to explicitly understand its history to implement public policies that prevent past errors from reoccurring.”

Last week, Brazilian Foreign Minister Aloysio Nunes, himself a former militant exiled during the dictatorship, complied with Herzog's request and formally asked that the U.S. State Department hand over all documents pertaining to the assassination and torture of Brazilians at the time. 

A State Department spokesperson said the department routinely considers such calls for declassification of documents and such requests are subject to review.

Still, some here are questioning the validity of the events described in the memo. In an interview with Brazil's Estadão newspaper, President Michel Temer expressed skepticism. “I thought the story was very strange,” he said. “Not everything that the CIA says is necessarily true, or an absolute truth.”

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