Lawyers likely to argue that entire case has effectively been voided BARRIE MCKENNA WASHINGTON -- Kenneth Lay's sudden death could prove to be an unexpected legal bequest to Jeffrey Skilling, his co-defendant in the landmark Enron Corp. fraud case. Mr. Skilling's legal team will almost certainly invoke Mr. Lay's demise to try to reverse his own fraud and conspiracy conviction or demand a retrial, legal experts said yesterday. That's because Mr. Lay's death Wednesday of an apparent heart attack effectively voids the entire case against the Enron founder, including the guilty verdict. Mr. Skilling, the former Enron chief executive officer...