Planning the Prosecution of U.S. War Criminals

Why can't the Dean of a law school, or any other seasoned lawyer for that matter, provide the precise steps to establish jurisdition to prosecute the president of the United States for murder? It baffles and scares the hell out of me that no one in the legal community seems to know what to do to bring our own leaders to justice! If our laws regarding this are so ambiguous, then I believe any local government, city, county or state should be able to move forward in bringing the murder charges against George W. Bush.