The investigating police officer is supposed to furnish details regarding day to day progress in the case under investigation in chronological order. A case diary maintained in a haphazard manner is bound to defeat the very purpose for which it is required to be maintained.
This section does not require that any statements made by witnesses should be recorded in the case diary.
The Supreme Court in Behari Prasad v. State of Bihar, observed that non- examination of the accused by investigation officer would not be a sufficient ground to fail the prosecution case, if offence against the accused has been clearly established by the account given by eye-witnesses which was in conformity with the first information report and medical evidence adduced in the case. In this case, the accused was convicted for the offence of murder on the basis of evidence gathered from eye-witnesses and medical report etc.
Deprecating the procedure adopted by the trial Court in the case of Sidharth v. State of Bihar, the Apex Court held that confidentiality is, always kept in the matter of criminal investigation and it is not desirable to make available the entire case diary to the accused.
In the instant case, Supreme Court had noticed that the entire case diary was given to the accused and the investigating officer was extensively cross-examined on many facts which were not very much relevant for the purpose of the case. The learned Sessions Judge should have been careful in seeing that the trial of the case was conducted in accordance with the provisions of Section 172 of the Code of Criminal Procedure.
The case diary maintained by the Investigation Officer cannot be used as evidence of any date, fact or statement contained therein. It can only be used by the Court for further elucidation of points which need clarification in the interest of justice.
The Supreme Court in Mohd. Ankoos v. Public Prosecutor, High Court of A. P., held that the prosecution cannot be permitted to make use of case diary to overcome the contradictions pointed out by the defence. Therefore, the acceptance of evidence of prosecution witnesses by the High Court by verifying their statements recorded in the case diary under Section 161 (3) was held to be illegal.