Section 64 embodies the general principle that the document must be proved by its primary evidence unless secondary evidence is permitted by Section 65.
The rule is applicable only to prove the contents of document. Primary evidence means the original document. When a party wants to prove the contents of a document he is required to produce the original document before the Court “where the contents of any document are in question, either as a fact directly is issue or a sub-alternate principal fact, the document is the proper evidence of its own contents”.
According to Section 61 the contents of a document may be proved either by primary evidence (Section 64) or by secondary evidence (Section 65). It is only when the primary evidence is not available the secondary evidence may be allowed to be produced. But when original document is under the custody of a person who was producing certified duly executed is admissible. It is said that the rule under section 64 is only applicable to the contents of document. It means that the contents of document must be proved by primary evidence.
The document which is otherwise inadmissible cannot taken in evidence only because no objection to the admissibility thereof was taken. The document containing the settlement should have been produced being a primary evidence. Once a document is properly admitted its content are also admitted in evidence though they may not be conclusive. When a deed of partition was admitted in evidence without objection, the question of admissibility cannot be raised at the stage of arguments. Where the objection is not that the document is inadmissible but that the mode of proof is irregular or insufficient the objection should be taken at the beginning of trial.