FILE - An unidentified person leaves Enron Corp. headquarters in Houston at the end of the day Jan. 22, 2002. (AP Photo/Pat Sullivan, File)

FILE - Richard Causey, Enron's former chief accounting officer, leaves the federal courthouse with his wife Elizabeth after being sentenced to five-and-a-half years in prison Wednesday, Nov. 15, 2006 in Houston. (AP Photo/David J. Phillip, File)