As Martha Stewart's trial moves into a third week, an important question remains unasked: Why are the feds prosecuting someone for receiving inside information, anyway? Isn't the criminal the corporate official who acts on knowledge that the public doesn't have? The government charges that on Dec. 27, 2001, Stewart learned from her broker that Samuel Waksal, the chief executive of ImClone Systems Inc., was trying to sell his stock because he knew that the Food and Drug Administration would announce an adverse decision the next day about his company's cancer drug, Erbitux. Stewart then sold her own 3,928 shares...