Article II Section 4.
The President, Vice President and all Civil Officers of the United States, shall be removed from Office on Impeachment for and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors.
Article III, Section 1
The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish. The Judges, both of the supreme and inferior Courts, shall hold their Offices during good Behaviour, and shall, at stated Times, receive for their Services, a Compensation, which shall not be diminished during their Continuance in Office.
Do believe the Constitution says something about they "Hold their office during good behavior. . . " One could -and I suspect rightly should insist "good Behavior " is interpreted as conducting their official acts as a reflection of their solmn Oath and according to the clear
language and intent of the US Constitution and laws pursuant to it(Foreign precedents and ideas NOT included)