Overview
Kangaroo court is an informal pejorative term for a court that ignores recognized standards of law or justice, carries little or no official standing in the territory within which it resides, and is typically convened ad hoc. A kangaroo court may ignore due process and come to a predetermined conclusion. The term is also used for a court held by a legitimate judicial authority, but which intentionally disregards the court's legal or ethical obligations (compare show trial).
A kangaroo court could also develop when the structure and operation of the forum result in an inferior brand of adjudication. A common example of this is when institutional disputants ("repeat players") have excessive and unfair structural advantages over individual disputants ("one-shot players").
Etymology
The term is known to have been used in the United States in 1841: an article in The Daily Picayune, New Orleans quotes the Concordia Intelligencer reporting several lynchings "upon various charges instituted by the Kangaroo court", asking "Don't comprehend: What is a Kangaroo court?" The term is not attested to have been used in Australia, native land of the kangaroo, or elsewhere before then.
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