Arthur Andersen has gone on trial for allegedly obstructing justice by shredding Enron-related documents.
The jury has been selected, and opening statements are expected today. The trial is expected to last at least three weeks.
The obstructing justice indictment accuses Andersen of destroying "tonnes of paper" and deleting computer files related to Enron.
At times, the US government says the destruction was so frenetic that employees worked overtime and shredding machines couldn't keep pace.
Prosecutors say Andersen should be convicted if jurors decide just one employee destroyed documents on the firm's behalf to thwart US government investigators.
Former Andersen partner and Enron lead auditor Mr David Duncan has already pleaded guilty to obstruction of justice. Mr Duncan admitted he directed document shredding to thwart the Securities and Exchange Commission's investigation into Enron.
"Documents were in fact destroyed so that they would not be available to the SEC," Mr Duncan said when he entered his plea.
But Andersen attorney Mr Rusty Hardin says he believes the US government will not be able to prove its case. "I don't think there's going to be any evidence in this case that people destroyed documents to keep them away from the police," Mr Hardin said.
PA