WaPo:

A federal judge in Houston yesterday wiped away the fraud and conspiracy conviction of Kenneth L. Lay, the Enron Corp. founder who died of heart disease in July, bowing to decades of legal precedent but frustrating government attempts to seize nearly $44 million from his family.
The ruling worried employees and investors who lost billions of dollars when the Houston energy-trading company filed for bankruptcy protection in December 2001. It also came more than a week after Congress recessed for the November elections without acting on a last-ditch Justice Department proposal that would have changed the law to allow prosecutors to seize millions of dollars in investments and other assets that Lay controlled.

[..]Legal analysts said Lake's ruling closely hewed to a long-held doctrine called abatement, which allows a conviction to be vacated if defendants die before they are able to exercise their right to appeal. Courts typically rule that defendants' constitutional rights to challenge their convictions outweigh other considerations, and the law hesitates to punish the dead, the analysts said. Read on...