Irregular investigation under corruption law does not vitiate conviction absent prejudice or miscarriage of justice.

An irregularity in investigation, including a trap conducted by an officer below the prescribed rank under the corruption statute, does not by itself vitiate the conviction. Where the Magistrate had authorised immediate investigation and the record showed no prejudice to the accused or miscarriage of justice, the conviction could not be disturbed merely because of the initial procedural defect. The later investigation by a higher officer and the limited corrective direction of the trial court did not undo the already laid trap, and the challenge to the sanction and investigation therefore failed.

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Issues: Whether the investigation and trap conducted by a police inspector below the designated rank, pursuant to the Magistrate's permission under the corruption statute, vitiated the conviction in the absence of shown prejudice or miscarriage of justice.

Analysis: The Magistrate had treated the matter as requiring immediate investigation and granted permission on that basis. Even assuming some irregularity at the initial stage because the investigation and trap were conducted by an officer below the prescribed rank, the record did not show any prejudice to the accused. The subsequent investigation by a higher officer and the trial court's limited corrective direction could not undo the trap already laid, and the conviction could not be set aside merely because of an irregularity in investigation unless it resulted in miscarriage of justice.

Conclusion: The investigation did not vitiate the conviction, and the challenge to the validity of the sanction and investigation failed.

Ratio Decidendi: An irregular investigation does not by itself invalidate a conviction unless the accused shows that the irregularity caused prejudice or a miscarriage of justice.

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