Guest Post: The Trajectory of Credibility - Forensics, Suspicion, and the Future of Circumstantial Justice in India

(This is a Guest Post by Sumedha Edara)

Could the Supreme Court’s decision in Vaibhav v. State of Maharashtra (2025 INSC 800) mark a pivotal shift in Indian criminal law jurisprudence? The context is as such – Mangesh, a medical student, passed away from a gunshot fired by the service pistol of his friend, Vaibhav’s father who was serving as a police officer. Both the Trial Court and the Bombay High Court convicted Vaibhav of murder by relying on his conduct post the incident—removing the body, cleaning bloodstains, and feigning ignorance—which they treated as incriminating “subsequent conduct” under Section 8 of the Indian Evidence Act 1872.

While the judgment itself confines its reasoning to established doctrines (Section 8’s evidentiary logic, forensic analysis, and prosecutorial burden) this article advances an interpretive framework, reading Vaibhav as signalling a transition from “suspicion justice” to “forensic rationalism” in criminal adjudication. What follows is a conceptual structure: the “Trajectory of Credibility,” organising judicial reasoning around forensic coherence, behavioural plausibility, and probability of motive. This analytic extension draws on comparative jurisprudence and psychological insights, situating the case as both doctrinal correction and a node for broader institutional debates.

The Judgement: Three Transformative Moves

The Court’s reasoning can be distilled into three moves which, while based purely on evidentiary doctrine, benefit from a closer reading between the lines to highlight broader themes that are implied:

i. The Limits of Conduct

The first move was to restrict conduct-based inferences under Section 8 of the IEA. The Trial Court and High Court had treated the acts of concealment as determinative of guilt. Their reasoning was circular – because the conduct was incriminating, it proved guilt; but because guilt was presumed, the conduct appeared incriminating. The Supreme Court broke this cycle by reaffirming that Section 8 only establishes relevance and not sufficiency. Conduct, while it may corroborate existing proof, cannot fill evidentiary gaps.

Importantly, the Court explained that conduct is “equivocal”, meaning that the same act may admit multiple readings. A frightened teenager may conceal evidence out of panic rather than guilt too. By ignoring this duality, the High Court arguably failed to fully adhere to the time-tested principle that for any conviction on circumstantial evidence there must be one hypothesis only, and that must be one of conclusive guilt. In Vaibhav, there was no such unequivocal conclusion: no ballistic confirmation, no motive, no eyewitness, and so no singular conclusion.

In clarifying the distinction between relevance and sufficiency, the Supreme Court rejected reliance only on conduct to establish guilt. I interpret this move as a step away from "suspicion justice"- where behavioural shortcuts substitute for concrete evidence as required by the law - using the judgment as a basis for further conceptual reflection. Such an interpretation repositions Section 8 as an evidentiary aid and not a judicial crutch.

ii. Forensic Trajectory as the Decisive Narrative

The second move was to foreground the factual significance of ballistic trajectory, rather than the accused’s conduct. This fact had not been considered below, by virtue of the pistol belonging to the accused’s father, chances of it being an “accident” are irrelevant. This conflated ownership of the weapon with the authorship of the act itself. The Supreme Court treated this as a fundamental flaw and held that the witnesses’ testimony regarding the bullet trajectory was clear and trustworthy, because only such an account led to any coherence in determining the chain of events that took place. In doing so, the Court effectively established that a trajectory analysis cannot be reduced to entry and exit wounds, and that the HC’s failure to grasp this was not a technical error but one that revealed a collapse of reliance of forensic literacy. Although the Court stopped short of theorising this as a broader principle, its reasoning implicitly restores the role of scientific coherence as central to criminal adjudication.

iii. The Re-embedding of Burden of Proof

The third and perhaps most constitutionally significant move was assertion of prosecutorial burden. The High Court had held that the burden of proof lay with the accused in explaining how the pistol had reached victim's hand and why he had concealed the evidence. This approach effectively inverted the doctrine of presumption of innocence. The Supreme Court restored the doctrinal balance in its judgement, reaffirming that the burden lies on the prosecution to first establish guilt beyond reasonable doubt before one turns to the accused for explanations. The accused’s obligation is always one of plausibility, not certainty. We are reminded here that silence or implausibility on part of the accused cannot rescue a weak case for the prosecution. Proof is the State’s burden and doubt is the citizen’s entitlement.

Together, these three reasonings by the Supreme Court successfully righted the wrongs that have been committed by the lower courts in adjudicating this case, and consequently, their broader implications have also reaffirmed evidentiary law’s true nature – conduct is only corroborative, science is decisive, and burden is constitutional.

The Test of "Trajectory of Credibility"

Drawing upon the judgment, I introduce here a conceptual “Trajectory of Credibility” framework, meant as a tool for analysing circumstantial evidence cases. It demands that the credibility of evidence must be followed along several axes until it reaches its destination, much like the path of a bullet.

The first is forensic coherence. It demands that courts ask whether scientific traces like ballistics, pathology, DNA, etc., can sustain guilt independently. In this case, the prosecution story was refuted by forensic evidence which showed that the bullet's upward trajectory indicated accidental discharge rather than homicide, proving that doubt endures where coherence fails.

Plausibility of behaviour is the second axis. Human psychology, cultural background, and stress response must all be taken into consideration when interpreting post-crime behaviour. Concealment may signal guilt, but it may also reflect panic. In this case, the accused’s conduct was reinterpreted as acts of a frightened student fearing his father who was a police officer. Behaviour of such sort is punishable under Section 201 of IPC, but not probative of murder.

The third axis is probability of motive. Courts must determine if the record reveals any animosity or a legitimate motive. The cases of Anwar Ali v. State of HP (2020) and Nandu Singh v. State of MP (2022) demonstrate that while lack of motive is not always fatal per se, its complete absence in cases based on circumstantial evidence tilts the scales in favour of acquittal. The same happened in this case, where a lack of animosity between the victim and accused weakened the hypothesis of guilt pointed towards the accused.

Only when these axes converge does the judicial trajectory close around guilt. Where they diverge, as in this case, an acquittal is constitutionally mandated.

Structural Gaps Exposed

The case also exposes the fragility of India’s judicial infrastructure. The judgement revealed not only prosecutorial shortcomings but systemic deficits that simply cannot be ignored.

The most glaring one is the country’s forensic deficit. India’s Forensic Science Laboratories (FSLs) are chronically understaffed and underfunded. Reports of DNA samples lying unexamined for months or even years are common; ballistic reports are often unavailable, as in this case. The Malimath Committee Report (2003) and 239th Law Commission Report (2012) both flagged this weakness, yet capacity remains stagnant. Without timely forensic reports, cases tend to lean only on circumstantial suspicion, further raising risks of wrongful conviction.

A second gap lies in the overbreadth of application Section 8 of the IEA. While the Supreme Court in its judgement insisted on caution, trial courts remain free to overvalue conduct. The risk is amplified in a society where fear of police is pervasive, and acts like panic driven concealment or tampering of evidence is common.

Third, judicial trust in science arguably remains low. The High Court’s refusal to give due weight to the bullet's trajectory despite clear expert testimony on the same, exemplifies how courts can undervalue or misunderstand scientific evidence. This is not unique to this case. In the Aarushi Talwar case too, conflicting forensic reports left trial courts confused, producing faulty inferences. And in the Uphaar fire case, lack of technical expertise hampered fact-finding. Without systemic judicial training, scientific ambiguity, which is possibly a result of the lack of investment in the science out of the distrust as discussed, will continue to be resolved through intuition rather than expertise.

Finally, this case highlights the absence of accountability for investigative failures. No sanction or consequence followed the failure to obtain ballistic verification. Without any mechanisms to discipline such lapses, investigators, obviously, face little incentive to meet forensic standards.

Together, these gaps explain why suspicion has long substituted for science in India’s criminal justice system. The implications of this judgment can mark an affirming point in jurisprudence, but without institutional reform, its jurisprudential promise risks remaining aspirational.

Broader Implications

The resonance of this case lies not just in doctrine but also in its potential ripple effects across institutions.

For police, it may signal towards the end of shortcut investigations. In a system often driven by narrative first, science later policing, the judgment redirects energy towards scene preservation, evidence collection, and expert consultation.

For prosecutors, it may raise the evidentiary threshold. Plausible narratives are no longer sufficient without forensic ballast. Prosecutions must now secure scientific backing to their claims - a burden, but also a liberation from reliance on conjecture.

For defence counsel, this precedent may be a powerful shield. It provides a doctrinal justification to dismantle prosecutions hinging on conduct or silence. It also supplies and supports a vocabulary - “trajectory,” “probability,” “alternate narratives” - that empowers defense advocacy.

For the judiciary, the case may redefine judicial satisfaction. No longer can suspicion or silence tilt the scales. Conviction now demands for the convergence of forensic coherence, plausibility of conduct, and probability of motive. Judges are required to think less as moral arbiters and more as epistemic adjudicators.

The ripple effects may extend further. Law schools may finally learn to integrate criminal law with forensic science and psychology. Forensic institutions gain visibility and pressure to expand. Civil society and rights advocates gain a powerful precedent affirming that wrongful conviction is as grave as wrongful acquittal.

Conclusion

The judgment in Vaibhav v. State of Maharashtra reconstructs the logic of evidence. The Court restored forensic centrality, reaffirmed prosecutorial burden, and curtailed excessive reliance on Section 8 in order to re-ground criminal law in constitutional principles. It enforces epistemic discipline through its framework, which tests consistency across science, conduct, and motive: divergence forces acquittal, while alignment supports conviction. Its acknowledgment of suspicion bias - that concealment may be motivated by fear rather than guilt - is equally noteworthy. However, the ruling also revealed institutional flaws, including the misuse of Section 8, judicial illiteracy, a fragile forensic system, and an impunity for investigative errors. Without reform, suspicion risks continuing to masquerade as proof.