Because it has been used so rarely, and because it is a power entrusted to Congress, not the courts, impeachment as a legal process is poorly understood. There are no judicial opinions that create precedents for how and when to proceed with it. Past cases are subject to competing and often contradictory interpretations. Some might even be tempted to argue that because impeachment is ultimately political, it cannot be considered in legal terms at all. That extreme view cannot be right. Impeachment must be a legal procedure because it derives from specific constitutional directives.