First attested 1853 in a Texas context, possibly from the notion of proceeding by leaps or because the kangaroo's appearance defies nature.
- (idiomatic) A judicial or quasi-judicial proceeding, or a group which conducts such proceedings, which is without proper authority, abusive, or otherwise unjust.
1856, Alfred W. Arrington, The Rangers and Regulators of the Tanaha, or, Life Among the Lawless: A tale of the republic of Texas., New York: R.M. DeWitt, page 247:
- Sol Tuttle interposed, "Don't you let nobody hev any witnesses in this kangaroo court?"
1933 April 10, “The New Pictures: M by Fritz Lang”, in Time:
- They take him off to face their kangaroo court in the cellar of a deserted brewery.
2003, David Glazier, “Kangaroo Court or Competent Tribunal?: Judging the 21st Century Military Commission”, in Virginia Law Review, volume 89, number 8, page 2093:
- A military commission trial falling short of the full UCMJ standard is all but certain to be pejoratively judged as a "kangaroo court" in the court of public opinion.
an unjust (quasi-)judicial proceeding or group