kangaroo court

American  

noun

1. a self-appointed or mob-operated tribunal that disregards or parodies existing principles of law or human rights, especially one in a frontier area or among criminals in prison.

2. any crudely or irregularly operated court, especially one so controlled as to render a fair trial impossible.

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kangaroo court British  

noun

1. an irregular court, esp one set up by prisoners in a jail or by strikers to judge strikebreakers

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kangaroo court Cultural  

1. A court that ignores principles of justice; a court characterized by incompetence and dishonesty.

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kangaroo court Idioms  

1. A self-appointed tribunal that violates established legal procedure; also, a dishonest or incompetent court of law. For example, The rebels set up a kangaroo court and condemned the prisoners to summary execution, or That judge runs a kangaroo court—he tells rape victims they should have been more careful. This expression is thought to liken the jumping ability of kangaroos to a court that jumps to conclusions on an invalid basis. [Mid-1800s]

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Etymology

Origin of kangaroo court

An Americanism dating back to 1850–55

Example Sentences

It didn’t help that her husband—who’d known Hoxha when the two men were students together in Paris—was found guilty by a kangaroo court of plotting to overthrow the government.

From The Wall Street Journal • Nov. 30, 2025

Allies of Mr Johnson who have criticised the committee include former cabinet minister Nadine Dorries, who also described the committee on television as a "kangaroo court".

From BBC • Jun. 28, 2023

Put another way, even those who are hauled before a kangaroo court are sometimes guilty as charged.

From Washington Post • Mar. 27, 2023

“Students of American history will now be able to read the last chapter and see that what was done to Oppenheimer in that kangaroo court proceeding was not the last word.”

From New York Times • Dec. 16, 2022

Uncle Ben hitched his chair, and with much chuckling, recalled the "kangaroo court" the cowboys used to hold at night in camp.

From Slave Narratives: a Folk History of Slavery in the United States From Interviews with Former Slaves. Texas Narratives, Part 2 by Work Projects Administration