In the fictional Star Trek universe, Discommendation (in Klingon, naDHa'ghach) is a declaration by the Klingon High Council that an individual Klingon and his family are dishonored. Those who have been discommended are considered pariahs and traitors. They lose nearly all their rights under Klingon law - one of the few possible exceptions being the right of vengeance. Discommendation can be declared for those who commit serious crimes against others (DS9: The House of Quark), or Klingons may accept this status for reasons such as a member of their family committing serious crimes.
The ceremony is performed with the council forming a circle around the individual. The accused speaks the words "tlhIH ghIj jIHyoj (I fear your judgment)." Crossing his arms, the Chancellor will make the formal declaration "biHnuch (Coward)!", and rapidly turns around to face away from the individual. The other members of the council will then follow suit. The authority to remove an individual from this state, to restore honor to the individual and his or her family normally rests with the Chancellor.
The idea of Discommendation was first expressed in the Peter David novel Strike Zone. In this book, it was said that to take a Klingon's name from him meant the Klingon had no honor. To have one's name taken would be one of the worst punishments there would be in Klingon society.
Worf's DiscommendationIn the time leading up to the death of Chancellor K'mpec, the council had found out that Ja'rod, father of Duras had betrayed the Klingon outpost on Kithomer to the Romulans. In Klingon law, not only was Ja'rod a traitor, but his wife and offspring were as well. Because the Duras family was very politically powerful at the time, the council feared that to reveal the truth would cause civil war within the Empire. As a result, the council decided to blame Mogh, father of Worf and Kurn with that crime. When Worf learned of this, he went to Qo'nos to challenge the council's ruling that he and his family were traitors. The Enterprise crew soon got to the truth of the matter, and Captain Picard found Worf's old nurse. Picard and Worf confronted the council with this matter. The council was still unwilling to reveal the truth. Worf finally agreed to accept discommendation to protect that secret. The council allowed Kurn to continue to hide his true family name, so that Worf would have him in place when the time to reveal the truth came.
For the next one and a half years, most Klingons wanted nothing to do with Worf. Most Klingons would become quite offended and incensed when he came into their presence. Worf and his family became persona non grata, their name rarely mentioned.
After the death of K'mpec, two challengers arose to fight for his office (TNG: Redemption). They were Gowron and Duras. It was found that Duras had tried to assassinate Gowron by planting a bomb inside the arm of one of his agents. Worf's mate K'Ehleyr also discovered the truth during this time, and Duras killed her to keep her silent. Duras was killed by Worf in an act of vengeance. As a result, only Gowron remained as the main challenger for that office.
However, the Duras family was still quite powerful. When the time came to install Gowron as Chancellor, they started a brief civil war in the Empire. As Worf and Kurn had saved Gowron's life, he restored their honor. While Duras was willing to blame Worf for the crimes of his father, Worf found that he was unable to do so when offered to do the same to Duras' son Toral. Worf refused to kill Toral, and also refused to allow Kurn to kill Toral either. Worf found to do so would have made him no better than Duras. Worf told the council that the boy (Toral) had done him no harm, and that he would not kill Toral for the crimes of his family.