1[(1A) The statements of witnesses recorded during the course of investigation under section 161 shall be inserted in the case diary.
(1B) The diary referred to in sub-section (1) shall be a volume and duly paginated.]
(2) Any Criminal Court may send for the police diaries of a case under inquiry or trial in such Court, and may use such diaries, not as evidence in the case, but to aid it in such inquiry or trial.
(3) Neither the accused nor his agents shall be entitled to call for such diaries, nor shall he or they be entitled to see them merely because they are referred to by the Court; but, if they are used by the police officer who made them to refresh his memory, or if the Court uses them for the purpose of contradicting such police officer, the provisions of section 161 or section 145, as the case may be, of the Indian Evidence Act, 1872 (1 of 1872), shall apply.
Contents
Explanation
CrPC Section 172 mandates that every investigating officer (IO) must maintain an investigation diary. This diary serves as a chronological record of all the actions taken during the investigation of a crime. It is a crucial document that helps ensure transparency, accountability, and proper documentation of the investigation process. The investigation diary must include:- Details of the crime being investigated.
- Information about the suspects and witnesses.
- Actions taken by the IO, such as interrogations, searches, seizures, and collection of evidence.
- Details of any evidence found and its preservation.
- Dates and times of all investigative actions.
Illustration
Scenario: A theft case is being investigated. The IO, in his investigation diary, records the following:- Date and time of the crime reported.
- Details of the stolen items and the victim’s statement.
- Interrogation of the suspects, their alibis, and inconsistencies in their statements.
- Search of the suspects’ premises and recovery of stolen items.
- Collection of fingerprints from the crime scene.
- Witness statements obtained and their corroboration with other evidence.
Common Questions and Answers
Q1. What is the purpose of the investigation diary?
The investigation diary serves multiple purposes:- To ensure a transparent and accountable investigation process.
- To provide a chronological record of all actions taken.
- To assist the IO in remembering details of the investigation.
- To facilitate the preparation of charge sheets and other legal documents.
- To allow the court to understand the investigation process and evaluate the evidence.
Q2. Who can access the investigation diary?
The investigation diary is primarily intended for the IO’s use, but it can be accessed by:- The IO’s superiors.
- The prosecution team.
- The court.
- The defense counsel, with permission from the court.
Q3. What are the consequences of failing to maintain an investigation diary?
Failure to maintain an investigation diary can have serious consequences:- The IO may face departmental action for negligence.
- The investigation may be deemed incomplete or unreliable.
- The prosecution case may be weakened in court.
- The accused may be acquitted due to lack of proper evidence.


