Constitutional Grounds for Impeachment

As specified in the U.S. Constitution, the grounds for impeachment are: Treason, Bribery, or other High Crimes and Misdemeanors. These have specific definitions in the law and their meanings and applications have been constructed over the years by the courts.

Treason is statutorily defined in 18 U.S. Code § 2381 as follows: "Whoever, owing allegiance to the United States, levies war against them or adheres to their enemies, giving them aid and comfort within the United States or elsewhere, is guilty of treason and shall suffer death, or shall be imprisoned not less than five years and fined under this title but not less than $10,000; and shall be incapable of holding any office under the United States." A key word here is: "enemies", a term which implies an existing state of war.

Bribery is defined in the Common Law as follows: "The receiving or offering any undue reward by or to any person whomsoever, whose ordinary profession or business relates to the administration of public justice, in order to influence his behavior, and to incline him to act contrary to his duty and the known rules of honesty and integrity. Hall v. Marshall, 80 Ky. 552; Walsh v. People, 05 111. 05, 16 Am. Rep. 509; Com. v. Murray, 135 Mass. 530; Hutchinson v. State, 36 Tex. 294. The term 'bribery' now extends further, and includes the offense of giving a bribe to many other classes of officers; it applies both to the actor and receiver, and extends to voters, cabinet ministers, legislators, sheriffs, and other classes." A conviction for bribery often requires the existence of a specific quid pro quo or "something for something," a specific exchange of a political act or other official favor for something of value.

High Crimes and Misdemeanors is a term of legal art in common parlance at the time of the drafting of the Constitution and does not necessarily track with the modern sense of crimes and misdemeanors (e.g., shoplifting). As Alexander Hamilton noted at the time, this term refers to "...those offences which proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust. They are of a nature which may with peculiar propriety be denominated political, as they relate chiefly to injuries done immediately to the society itself." In other words, it is a catchall term for abuse of political power, a betrayal of the public trust, the obstruction or circumvention of justice, or even a failure to carry out the office holder's oath and duties of office. Historically, it has been applied to such diverse offenses as "misappropriating government funds, appointing unfit subordinates, not prosecuting cases, not spending money allocated by Parliament, promoting themselves ahead of more deserving candidates, threatening a grand jury, disobeying an order from Parliament, arresting a man to keep him from running for Parliament, losing a ship by neglecting to moor it, helping 'suppress petitions to the King to call a Parliament,' granting warrants without cause, and bribery"—not all of which are crimes under the law. Lindorff, Dave; Olshansky, Barbara (2006). The Case for Impeachment: The Legal Argument for Removing President George W. Bush from Office. New York, NY: St. Martin's Press. p. 38.