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World War III-style court
- TNG: 'Encounter at Farpoint' - Q charges Humanity of being a grievously savage race
Klingon legal system
ENT: 'Judgement' - Captain Archer is tried in a Klingon tribunal for attacking a Klingon ship and inciting a rebellion.
TOS: The Undiscovered Country - Kirk and McCoy are tried for assassination of Chancellor Gorkon
DS9: 'The House of Quark' - Grilka and Quark must establish Quark as the rightful leader of Grilka's house before The Klingon High Council.
TNG: 'Sins of the Father' - Worf must defend his family's honor before the high council, while Picard acts as his Cha'DIch.
TNG: 'Reunion' - The dying emperor K'mpec chooses Picard to arbitrate the Rite of Succession, in which either Duras or Gowron will become the next emperor.
Cardassian legal system
- DS9: 'Tribunal' - O'Brien is charged with selling weapons to the Maquis.
Bajoran legal system
- DS9: 'Dax' - Jadzia Dax is the subject of an extradition hearing over an accusation of murder against Dax's former host, Curzon.
Ferengi legal system
- DS9: 'Body Parts' - Quark has his Ferengi Business License summarily revoked by the Ferengi Commerce Authority, in the person of Brunt, for breaking a contract.