The company is seeking records of eight bank accounts at the Banco Pichincha, an Ecuadorean bank with a branch in Miami that Chevron says was a conduit for $360,000 in "illicit payments" to the independent expert, Richard Cabrera.

Cabrera was appointed by a court in Ecuador to examine oil exploration pits environmental groups say caused massive pollution to the surrounding rain forest and sickened indigenous residents. Chevron was sentenced by a court in Ecuador to pay $18 billion for environmental damages.

"What we are seeking is a little sunshine," Andrea Neuman, a lawyer for Chevron told U.S. District Court Judge William Turnoff. "We need to know what this money was used for."

Chevron alleges that recent court-ordered discovery of documents have turned up "significant evidence of fraud and collusion" in the case.

"Evidence already obtained by Chevron shows that these accounts were likely used to secretly pay the supposedly independent court-appointed expert Richard Cabrera in furtherance of the plaintiffs' scheme to obtain a corrupt judgment against Chevron," said Chevron Corp spokesman Kent Robertson.

A lawyer for the bank argued that the request, if granted, would violate banking confidentiality laws in Ecuador and could result in the bank facing civil and criminal penalties. "They are asking the bank to violate the laws in Ecuador," said Clinton Losego, a lawyer for Pichincha.

Chevron is engaged in a desperate fishing expedition in a bid to avoid having to pay to compensate indigenous peoples for environmental damages, said Karen Hinton, a spokeswoman for the Amazon Defense Coalition, representing the plaintiffs.

"We won an $18 billion judgment against Chevron for massive oil contamination and are preparing to enforce it," said Hinton.

"This latest court action is nothing more than 11th hour hysteria by a company that has tried and will try every imaginable legal maneuver money can buy to deny justice to suffering people in the Ecuadorian rainforest."

There was nothing unusual about the payments to Cabrera, she said, explaining that the court ordered both the plaintiffs and Chevron to cover the costs of the independent expert's work.

"Chevron was supposed to pay him as well, but they boycotted the process. Now they are trying to make something out of nothing," she said.

The strands of litigation in the case have multiplied in the past three years. Chevron has brought the matter before an international tribunal, claiming Ecuador violated a trade treaty with the United States by not guaranteeing a fair trial for the company.

According to a quarterly financial filing by Chevron on Thursday, the tribunal decided last month it would hear by late November about the late-1990s settlement and release agreements between Texaco and Ecuador over the rainforest pollution, with the remaining issues to be heard later.

The original suit was between Ecuador and Texaco Inc. Chevron acquired Texaco for about $39 billion in 2001.

(Additional reporting by Braden Reddall in San Francisco; editing by Todd Eastham)

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