Code of the Ushaan
The Code of the Ushaan was the code of the Andorian combat to the death, the Ushaan. It described all the rules and terms of the Ushaan.

Referring to it as a "ridiculous honor code", Hoshi Sato stated that the Ushaan had 12,000 amendments, some involving ways to postpone or cancel a battle.

A key provision of the code was the "Right of Substitution", which allowed participants to select another to fight in their place. The Tellarite Naarg exercised this right to select Jonathan Archer as his replacement in the Ushaan against Thy'lek Shran.

One rule in the Code was that "Either combatant can postpone a duel indefinitely if there are no children to continue his clan."  This did not apply to Archer, since he would have had to be married in order to make use of the clause. Another, that did apply, was that the Ushaan could be determined to be settled if an opponent was rendered defenseless. When Archer chopped off one of Shran's e with his ushaan-tor, Archer invoked this rule. ()

Excerpt
Exemptions and Deferrals
Hardship Deferment
Either combatant can postpone a duel indefinitely if there is determined to be
sufficient hardship to justify the delay, pending approval by the opposing
combatant or combatant's proxy.

Religious Deferment
Either combatant can postpone a duel indefinitely based on specifically defined
religious objections, pending approval by the opposing combatant or combatant's
proxy. A member of any recognized religious order is forbidden from participating
in ritual combat and must instead submit his or herself to discipline by the
administrative body of the appropriate sect.

Ancestral Exemption
If a combatant's family history includes an act of heroism, sanctioned by no less
than three ranking government officials, said combatant may step down from the
challenge after making and agreed-upon monetary restitution.

Sibling Proxy
A sibling (male or female) of appropriate age that volunteer to take the place of a
combatant, pending approval by the opposing combatant or combatant's proxy.

Progeny Proxy
A son or daughter of appropriate age that volunteer to take the place of a
combatant, pending approval of the opposing combatant or combatant's proxy; and
if such substitution does not impose the clan contamination deferment.

Clan Continuation
Either combatant can postpone a duel indefinitely if there are no children to 
continue his clan (...)  ()

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