Coming to the use of police diary by the accused, sub-section (3) of Section 172 clearly lays down that neither the accused nor his agents shall be entitled to call for such diaries nor he or they may be entitled to see them merely because they are referred to by the Court. The entries in the police diary are neither substantive nor corroborative evidence, and that they cannot be used against any other witness than against the police officer that too for the limited extent. But, in case the police officer uses the entries in the diaries to refresh his memory or if the Court uses them for the purpose of contradicting such police officer, then the provisions of Sections 145 and 161, as the case may be, of the Evidence Act would apply. Section 145 of the Evidence Act provides for cross examination of a witness as to the previous statements made by him in writing or reduced into writing and if it was intended to contradict him in writing, his attention must be called to those portions which are to be used for the purpose of contradiction. Section 161 deals with the adverse party’s right as to the writing used to refresh memory. It can, therefore, be seen that, the right of the accused to cross-examine the police officer with reference to the entries in the police diary is very much limited in extent and even that limited scope arises only when the Court uses the entries to contradict the police officer or when the police officer uses it for refreshing his memory. In other words, in case if the Court does not use such entries for the purpose of contradicting the police officer or if the police officer does not use the same for refreshing his memory, then the question of accused getting any right to use entries even to that limited extent does not arise. The accused persons cannot force the police officer to refresh his memory during his examination in the Court by referring to the entries in the police diary. Right of the accused to cross examine the police officer with reference to the entries in the police diary is very much limited in extent and even that limited scope arises only when the Court uses such entries to contradict the police officer or when the police officer uses it for refreshing his memory and that again is subject to provisions of Sections 145 and 161 of the Indian Evidence Act. Thus, a witness may be cross-examined as to his previous statements made by him as contemplated under Section 145 of the Evidence Act if such previous statements are brought on record, in accordance with law, before the Court and if the contingencies as contemplated under Section 172(3) of Cr.P.C. are fulfilled. Section 145 of the Indian Evidence Act does not either extend or control the provisions of Section 172 of Cr.P.C. We may hasten to add here itself that there is no scope in Section 172 of the Cr.P.C. to enable the Court, the prosecution or the accused to use the police diary for the purpose of contradicting any witness other than the police officer, who made it.
From the afore-mentioned, it is clear that the denial of right to the accused to inspect the case diary cannot be characterized as unreasonable or arbitrary. The confidentiality is always kept in the matter of investigation and it is not desirable to make available the police diary to the accused on his demand……Balakram vs. State of Uttarakhand & Ors.
But if the entire case diary is made available to the accused, it may cause serious prejudice to others and even affect the safety and security of those who may have given statements to the police. The 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….Sidharth etc. etc. vs. State of Bihar, AIR 2005 SC 4352.