As per Lawkidunya, In Pakistan, the admissibility of documentary evidence is governed by the Qanun-e-Shahadat Order, 1984, and the Code of Criminal Procedure (CrPC), 1898. Here are the key principles:

Primary Evidence

1. Original document: The original document is the best evidence.
2. Certified copy: A certified copy of the document can be admitted if the original is not available.

Secondary Evidence

1. Photocopy: A photocopy of the document can be admitted if the original is not available.
2. Electronic copy: An electronic copy of the document can be admitted if the original is not available.

Requirements for Admissibility

1. Relevance: The document must be relevant to the facts of the case.
2. Authenticity: The document must be authentic and not tampered with.
3. Reliability: The document must be reliable and trustworthy.
4. Provenance: The document must be properly proven, i.e., its origin and history must be established.

Exclusions

1. Hearsay evidence: Documentary evidence that is based on hearsay is not admissible.
2. Privileged documents: Documents that are privileged, such as confidential communications between lawyer and client, are not admissible.
3. Unreliable documents: Documents that are unreliable or tampered with are not admissible.

Procedure for Admission

1. Notice: The party seeking to admit the document must give notice to the opposing party.
2. Objection: The opposing party can object to the admission of the document.
3. Ruling: The court will rule on the admissibility of the document.