538. […] The Appeals Chamber recalls that reference to principles applied in national jurisdictions can be of assistance to both Trial Chambers and the Appeals Chamber in interpreting provisions of the Statute and the Rules.[1]  However, Rule 89(A) of the Rules expressly provides that the Chambers “shall not be bound by national rules of evidence.”  What is of primary importance is that a Trial Chamber “apply rules of evidence which will best favour a fair determination of the matter before it and are consonant with the spirit of the Statute and the general principles of law.”[2]  The Appeals Chamber notes that the Trial Chamber found that implicit in this principle was “the application of national rules of evidence by the Trial Chamber.”[3]  On the contrary, the Appeals Chamber confirms that rules of evidence as expressly provided in the Rules should be primarily applied, with the assistance of national principles only if necessary for guidance in the interpretation of these Rules.