In suburban Georgetown a killer's Reeboks whisper on the front floor of a posh home. In a seedy D.C. porno house a patron is swiftly garroted to death. The next day America learns that two of its Supreme Court justices have been assassinated. And in New Orleans, a young law student prepares a legal brief. To Darby Shaw it was no more than a legal shot in the dark, a brilliant guess. To the Washington establishment it was political dynamite. Suddenly Darby is witness to a murder