SAO PAULO (Reuters) - When João Paulo de Oliveira was fired in 1980 by Rapistan, a Michigan-based manufacturer of conveyor belts, his troubles were only beginning.

In ensuing years, the military dictatorship that ran Brazil arrested or detained him about 10 times. Police cars passed by his house in São Paulo's industrial suburbs, he said, and officers would make throat-slashing gestures or wave guns at him.

Oliveira's apparent offense: Being a union organizer during an era when the military considered strikes to be tantamount to communist subversion.

"I used to joke that my house was the safest in the neighborhood, with all the police," said Oliveira, now 63. "But it was tough, really scary, like psychological torture."

Worse, he said, local manufacturers refused to hire him for years afterward, vaguely citing his past. Other colleagues met the same fate. "We always suspected the companies were passing information on us to the police," he said. "But we never knew for sure."

Newly uncovered evidence suggests that Oliveira's suspicions were well-founded.

A government-appointed commission investigating abuses during Brazil's 1964-1985 dictatorship has found documents that it says show Rapistan and other companies secretly helped the military identify suspected "subversives" and union activists on their payrolls. Among those named is Oliveira. The official report isn't scheduled to be released until December, but the commission allowed Reuters to review the evidence involving companies as the investigation nears its end.

Foreign and Brazilian companies are cited in the documents, including, most prominently, some of the world's biggest automakers: Volkswagen AG, Ford Motor Co, Toyota Motor Corp and the Mercedes-Benz unit of Daimler AG, among others.

No companies have been accused of any crimes. Whether they collaborated with the dictatorship, and to what extent, are in dispute. Nevertheless, human rights advocates and some of the workers named in the documents say they may pursue civil lawsuits or other legal action as a result of the commission's findings.

Some workers want the companies to pay reparations for lost wages. Others, including those who doubt the commission's findings will be conclusive enough for a court case, say they would be satisfied with an apology.

The National Truth Commission was created in 2012 by President Dilma Rousseff, herself a former leftist militant who was jailed and tortured by the military in the early 1970s.

The commission is tasked with shedding new light on abuses during that era and who was responsible for them. The U.S.-backed dictatorship killed some 300 people and tortured or imprisoned thousands more in what it saw as a fight to stop leftists from turning Brazil into a giant version of Fidel Castro's Cuba.

Rousseff, who is running for re-election in October, has expressed hopes that a fuller historical record will help ensure that Brazil, now a thriving democracy and rising economic power, never repeats that era's mistakes.

Businesses in general benefited from the dictatorship's conservative policies. Academics have long believed that local and multinational companies helped the regime identify employees who were fomenting labor unrest or otherwise posed a supposed threat to stability.

Now, the commission's researchers have discovered evidence that they believe proves such a relationship.



"THE BLACK LIST"

The documents do not provide a complete record of state repression during the dictatorship. Some papers from that period were burned by the military or otherwise vanished; some have been found in the past year in the homes of former officers after they died; others are scattered among state archives.

The commission's most prized discovery to date is a document found in São Paulo state's archives that researchers informally call "the black list."

The typewritten list contains the names and home addresses of some 460 workers from 63 companies in an area of Greater São Paulo that is sometimes called "Brazil's Detroit" because many foreign automakers are based there.