Federal employees are prohibited by law from discussing employment with a company while that company is involved in dealings with the government that could benefit it. They're also prohibited from "violating the public trust" by, for instance, giving contracts to friends or associates. The Feds are said to be looking into whether Norton broke either of those laws.
Norton's interior department also had ties to Jack Abramoff. The department's number 2, Steven Griles, pleaded guilty in 2007 to lying to investigators who were looking into whether Abramoff used a Norton aide -- who Griles was dating -- to improperly gain access to Norton and Griles.
Norton did not return National Journal's request for comment.