Enron's former chief accounting officer is expected to plead guilty this afternoon to one or more of the 34 criminal charges against him.
A source tells The Associated Press that Richard Causey has also agreed to testify against the company's top two executives in exchange for a lighter prison sentence.
Enron founder Kenneth Lay and former C-E-O Jeffrey Skilling are scheduled to go on trial next month without him. But with Causey now set to testify against them, their lawyers likely will seek a delay.
Causey had been charged with fraud, conspiracy, insider trading, lying to auditors and money laundering for allegedly knowing about or participating in a series of schemes to fool Enron investors.
When he was indicted last year, he pleaded innocent.