Enron rigged electricity prices to its own advantage during California's energy crisis, according to tapes aired by CBS News on Tuesday.
The tapes have national significance, as Enron chief executive Ken Lay is a friend of President George W Bush, who said during the crisis that he would not cap California's rocketing energy prices.
The recording, obtained from the US Justice Department, are of Enron employees apparently scheming to shut down power plants as California's electricity prices went sky-high.
"If you took down the steamer, how long would it take to get it back up?" Enron worker said on the recording played by CBS.
"Oh, it' s not something you want to just be turning on and off every hour. Let's put it that way," another says.
"Well, why don't you just go ahead and shut her down?"
CBS said a public utility in Snohomish, Washington, near Seattle had obtained the tapes from the Justice Department.
"This is the evidence we've all been waiting for. This proves they manipulated the market," a utility spokesman told CBS.
The utility is one of thousands of people and businesses who would like to get their money back.
"They're [expletive] taking all the money back from you guys? All the money you guys stole from those poor grandmothers in California?" asks an Enron trader on the tapes.
"This is the evidence we've all been waiting for. This proves they manipulated the market"
"Yeah, grandma Millie, man," said another. "Yeah, now she wants her [expletive] money back for all the power you've charged ... for [expletive] 250 dollars a megawatt-hour."
CBS also reported that the tapes appear to tie Lay and Jeffrey Skilling to schemes that fuelled the crisis.
Enron workers on the tapes spoke of Lay's access to Bush as the president named his cabinet in 2001. "Ken Lay's going to be Secretary of Energy," one Enron worker said.
CBS said that the Justice Department and Enron fought to prevent release of the tapes. Enron lawyers told the network that the only thing the tapes prove is "that people at Enron sometimes talked like Barnacle Bill the Sailor."