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Supreme Court of India
NDPS Act

Informant Investigating the Case Does Not by Itself Vitiate Trial: Supreme Court Constitution Bench Overrules Mohan Lal

Published: · NyayVidhan

A five-Judge Constitution Bench of the Supreme Court held that an investigation is not vitiated merely because the informant or complainant police officer also investigated the case, and the accused is not entitled to acquittal on that ground alone (para 12). Bias or prejudice depends on the facts of each case and has to be established, not inferred (paras 11-12). The Bench overruled Mohan Lal v. State of Punjab and confined three earlier acquittals to their own facts (para 12).

Informant Investigating the Case Does Not by Itself Vitiate Trial: Supreme Court Constitution Bench Overrules Mohan Lal

Judgment Intelligence

Other
Mukesh Singh v. State (Narcotic Branch of Delhi)
Special Leave Petition (Criminal) Diary No. 39528/2018 with SLP (Crl.) Nos. 5648/2019, 5894/2019 and 8499/2019; reported as 2020 SCC OnLine SC 700
Court
Supreme Court of India
Date of Decision
31 August 2020
Bench
Justices Arun Mishra, Indira Banerjee, Vineet Saran, M.R. Shah and S. Ravindra Bhat (Constitution Bench)
Relevant Acts & Sections
Narcotic Drugs and Psychotropic Substances Act, 1985 — Sections 35, 42, 52, 53, 54, 58, 68; Code of Criminal Procedure, 1973 — Sections 154, 156, 157, 465; Indian Evidence Act, 1872 — Section 114, illustration (e); Constitution of India — Article 21
Final Outcome

The reference was answered accordingly, and the petitions were directed to be placed before the appropriate Court for decision on merits in light of the answer (paras 12-14).

Key holdings

  1. Merely because the informant is the investigator, the investigation does not suffer from unfairness or bias, and the accused is not entitled to acquittal on that sole ground (para 12).
  2. Mohan Lal v. State of Punjab, (2018) 17 SCC 627, and any decision holding that the informant cannot be the investigator are not good law and are overruled (para 12).
  3. Bhagwan Singh, Megha Singh and Rajangam are confined to their own facts and lay down no general rule (paras 8, 12).
  4. Neither the CrPC nor the NDPS Act bars the informant from investigating; Section 53 of the NDPS Act permits it (paras 9.1, 9.5, 11).
  5. Bias or prejudice has to be established, not inferred; if proved where the case rests only on the informant-investigator, it can be given due weightage (para 11).

Brief Facts

In Mohan Lal v. State of Punjab, (2018) 17 SCC 627, the Court had held that where the police officer who is the complainant also conducts the investigation, the trial is vitiated and the accused is entitled to acquittal (opening paragraph). A three-Judge Bench in Varinder Kumar v. State of Himachal Pradesh later made Mohan Lal prospective, leaving pending prosecutions, trials and appeals to their own facts (para 2). Doubting Mohan Lal, a Bench referred the matter to three Judges on 17.01.2019, and a three-Judge Bench referred it to five Judges on 12.09.2019 (opening paragraph). The question was whether an investigation by the informant police officer vitiates the trial and entitles the accused to acquittal (para 8).

Court's Findings

Bhagwan Singh and Megha Singh were decisions on their own facts, where the evidence was doubted and independent witnesses were absent, and Rajangam merely followed Megha Singh (paras 8.1.1-8.1.3). Mohan Lal had not considered in detail Sections 154, 156, 157 and 465 CrPC, Section 114 of the Evidence Act, the need for the accused to show prejudice, or the scheme of the NDPS Act (para 8.1.4). The Bench agreed with V. Jayapaul, S. Jeevanantham and Bhaskar Ramappa Madar that investigation by the informant is not barred and can be assailed only for bias on the facts (paras 8.2.1-8.2.3, 11). Under Section 157 CrPC an officer in charge may investigate "either on information or otherwise" (para 9). The NDPS Act does not bar the informant from investigating; Section 53 permits it (paras 9.4-9.5). Fairness is tested at trial, where the informant is cross-examined and police evidence is weighed like any other (para 10). Official acts are presumed regularly done, Section 58 punishes vexatious or malicious action, and the reverse burden under Sections 35 and 54 operates only after the prosecution's initial burden is met (paras 10.1-10.3).

Legal Principle

An investigation is not vitiated, and the accused is not entitled to acquittal, merely because the informant is also the investigator. Bias or prejudice depends on each case's facts and must be proved; where it is proved and the prosecution rests only on the informant-investigator's evidence, that can be given due weightage (paras 11-12).

Precedents Relied Upon

  1. Mohan Lal v. State of Punjab (2018) 17 SCC 627
    Overruled Discussed at ¶ 2, 8, 10, 12

    Held that where the investigation is conducted by the police officer who is himself the complainant, the trial is vitiated and the accused is entitled to acquittal; overruled as not good law.

  2. Varinder Kumar v. State of Himachal Pradesh (2020) 3 SCC 321
    Referred To Discussed at ¶ 2, 8

    A three-Judge Bench held that Mohan Lal applies prospectively, pending prosecutions, trials and appeals being governed by their individual facts; the Constitution Bench still decided the question on its merits.

  3. Bhagwan Singh v. State of Rajasthan (1976) 1 SCC 15
    Explained Discussed at ¶ 8, 12

    The acquittal, where the Head Constable who was offered the bribe lodged the FIR and investigated, rested on its own facts and lays down no general rule that the informant can never investigate.

View all precedents (18)
  1. Megha Singh v. State of Haryana (1996) 11 SCC 709
    Explained Discussed at ¶ 8, 12

    The observation that the complainant Head Constable should not have investigated was made on the peculiar facts after the evidence was doubted; confined to its own facts.

  2. State by Inspector of Police, NIB, Tamil Nadu v. Rajangam (2010) 15 SCC 369
    Explained Discussed at ¶ 8, 12

    The acquittal followed Megha Singh without further discussion; confined to its own facts.

  3. State v. V. Jayapaul (2004) 5 SCC 223
    Followed Discussed at ¶ 8, 11

    Investigation by the police officer who lodged the FIR is not barred; it can be assailed only for bias or real likelihood of bias, which depends on the facts of each case.

  4. S. Jeevanantham v. State (2004) 5 SCC 230
    Relied Upon Discussed at ¶ 5, 8

    In an NDPS case, a conviction was not set aside although the complainant officer investigated, as no prejudice or bias was shown.

  5. Bhaskar Ramappa Madar v. State of Karnataka (2009) 11 SCC 690
    Followed Discussed at ¶ 8, 11

    There is no legal bar against investigation by the complainant; the matter is decided case by case without universal generalisation.

  6. State of U.P. v. Bhagwant Kishore Joshi AIR 1964 SC 221
    Referred To Discussed at ¶ 8

    Considered in V. Jayapaul on the scheme of Sections 154, 156 and 157 CrPC.

  7. Referred To Discussed at ¶ 8

    Noted in Mohan Lal as one of the decisions on the other side of the conflict.

  8. Referred To Discussed at ¶ 5, 8

    Cited among decisions holding that investigation by the complainant does not vitiate the investigation.

  9. Lalita Kumari v. Government of Uttar Pradesh (2014) 2 SCC 1
    Relied Upon Discussed at ¶ 9

    Section 154 leaves the police no discretion to hold a preliminary enquiry; the information must be recorded and then investigated.

  10. Karamjit Singh v. State (Delhi Administration) (2003) 5 SCC 291
    Relied Upon Discussed at ¶ 10

    Testimony of police personnel is treated like that of any other witness and needs no independent corroboration as a rule of law.

  11. Devender Pal Singh v. State (NCT of Delhi) (2002) 5 SCC 234
    Relied Upon Discussed at ¶ 10

    The presumption that a person acts honestly applies to a police officer too; he is not to be distrusted without good grounds.

  12. State of Rajasthan v. Ram Chandra (2005) 5 SCC 151
    Relied Upon Discussed at ¶ 6, 11

    The question of prejudice or bias has to be established and not inferred.

  13. Union of India v. Vipan Kumar Jain (2005) 9 SCC 579
    Relied Upon Discussed at ¶ 6, 11

    The question of bias has to be decided on the facts of each case.

  14. Referred To Discussed at ¶ 6

    Cited by the Additional Solicitor General as approving V. Jayapaul where the investigating officer had seized the opium.

  15. State of Punjab v. Noor Aga (2008) 16 SCC 417
    Referred To Discussed at ¶ 6

    Cited by the Additional Solicitor General: presumptions against the accused operate only after the foundational facts are established.

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Court Judgments · 3 min read
Decided: August 31, 2020 Justices Arun Mishra, Indira Banerjee, Vineet Saran, M.R. Sh...
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