Final answer:
The code of arbitration is not used in situations where there is a conflict of interest, such as when a governing body or legislative body must judge on matters in which they have personal interests. This is highlighted by historical examples and the principle that one cannot be a judge in their own cause.
Step-by-step explanation:
The code of arbitration is designed to resolve disputes, but there are limitations on its scope. It would not be used to resolve disputes between entities or individuals where there is an inherent conflict of interest. For example, the Kamakura shogunate would not take complaints against itself from its own vassals, nor would it act of its own accord. Additionally, it could not serve as both judge and party in a dispute, because this would compromise the necessary impartiality required for justice. In the broader context, just as no man should be a judge in his own cause, a body of men (such as a legislative body) should not judge matters in which they have a personal interest. This concept is derived from the need for impartiality in legislation, where decisions must be free of personal biases and should serve the public good.