A kangaroo court is a judicial tribunal or assembly that blatantly disregards recognized standards of law or justice, and often carries little or no official standing in the territory within which it resides. The term may also apply to a court held by a legitimate judicial authority who intentionally disregards the court's legal or ethical obligations.
A kangaroo court is often held to give the appearance of a fair and just trial, even though the verdict has in reality already been decided before the trial has begun. This could be because of the biases of the decision-maker, or because 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").
Although the term kangaroo court has been erroneously explained to have its origin from Australia's courts while it was a penal colony, the first published instance is from an American source in the year 1853. Some sources suggest that it may have been popularized during the California Gold Rush of 1849, along with mustang court, as a description of the hastily carried-out proceedings used to deal with the issue of claim jumping miners. Ostensibly the term comes from the notion of justice proceeding "by leaps", like a kangaroo – in other words, "jumping over" (intentionally ignoring) evidence that would be in favour of the defendant. Another possibility is that the phrase could refer to the pouch of a kangaroo, meaning the court is in someone's pocket. The phrase is popular in the UK, US, Australia and New Zealand and is still in common use.
The term is sometimes used without any negative connotation. For example, many Major League Baseball teams have a kangaroo court to punish players for errors and other mistakes on the field, as well as for being late for a game or practice, not wearing proper attire to road games, or having a messy locker in the clubhouse. Fines are allotted, and at the end of the year, the money collected is given to charity. The organization may also use the money for a team party at the end of the season.
Some examples of adjudication venues described as kangaroo courts are the People's Court (Volksgerichtshof) that convicted people who were suspected of being involved with the failed plot to assassinate Hitler on July 20, 1944, clinical peer review, and the Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism military tribunals.