History
Congressional subpoenas directed at Supreme Court Justices are exceedingly rare, underscoring respect for the separation of powers. One notable event involved Associate Justice Thomas C. Clark in 1953, when the House Un-American Activities Committee issued a subpoena for his testimony. This subpoena sought information related to his actions as Attorney General before his Supreme Court appointment, not his judicial conduct. Justice Clark voluntarily appeared, but the subpoena’s enforceability regarding a sitting Justice’s judicial duties was not definitively tested.
The only Supreme Court Justice to be impeached was Samuel Chase in 1804, though he was acquitted by the Senate. While impeachment is a congressional check on the judiciary, it differs from a subpoena for testimony or documents. The rarity of such direct confrontations reflects a historical understanding that compelling a Justice’s testimony could infringe upon judicial independence.
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