The Politics of Proof

**Pranav Saraf

Some of the most consequential disputes encountered by the modern Indian Court system are now determined by expert evidence. It also helps locate the Best Evidence Rule within trials. The rule requires the Court to prefer primary materials over secondary, explaining why witnesses ordinarily testify only to what they perceive rather than to the conclusions they draw. 

Expert evidence, therefore, occupies a distinctive and conditional role because it brings specialised knowledge into the Court while remaining advisory in nature. For instance, criminal prosecutions resting on DNA and digital traces, regulatory litigation invoking economic or scientific models, and family or public policy disputes where psychology, anthropology or sociology are relied upon. 

The Bharatiya Sakshya Adhiniyam (“BSA”), 2023, broadened the statutory scope of who qualifies as an “expert.” Where the Indian Evidence Act, 1872 (“IEA”) listed a few limited categories (foreign law, science, art, handwriting/fingerprint identification), the BSA explicitly allows opinions from experts in “any other field.” 

This paper argues that while the BSA’s expansion is necessary, it should be paired with institutional safeguards as well as procedural gatekeeping based on practices in other countries, most notably the United States’ (“US”) Federal approach under Rule 702 and Daubert/Kumho and the United Kingdom’s (“UK”) institutionally and procedurally layered approach. It conditions admissibility on demonstrable reliability and creates procedural mechanisms such as preliminary hearings, mandatory disclosures, and neutral experts to test methodology. 

The paper proceeds in five parts. Part I briefly discusses colonial practices of using experts through the work of Elizabeth Kolsky. Part II analyses the BSA against the IEA. Part III identifies risks that follows the statutory shift. Part IV explains the US gatekeeping regime, its supporting infrastructure, and the UK’s. Part V proposes legislative, procedural, and institutional reforms on a priority basis based on the US and the UK models.

Colonial History

Colonial anxieties about the “truthfulness” of Indian witnesses shaped not only policing and procedure but the very kinds of evidence colonial Courts relied on. Indians were often described as habitually deceitful by the British. This perception became a practical problem for the colonisers attempting to govern without trusting local testimony. As Kolsky shows, officials complained as early as the 1820s that “the great cause of failure in the administration of criminal as well as of civil justice is the habitual disregard for truth which unhappily pervades the bulk of the native community.”

Faced with this “mendacity” problem, colonial institutions sought technological and scientific substitutes for oral testimonies. Medical jurisprudence, fingerprinting, inquests and photography were promoted as “truth-technologies” that could elicit reliable facts independently of such unreliable witnesses. Kolsky traces how medico-legal practice grew rapidly in the nineteenth century: coroners, civil surgeons and police inquests came to play central roles in trials involving murder, poisoning and sexual offences, even before formal rules regulated the admissibility or the status that was to be accorded to such evidence. The result was a courtroom where “the body evidencing the crime” was increasingly preferred over oral testimony, reflecting a shift of administrative needs as much as scientific progress. 

Nevertheless, the medical-scientific literature developed in India was shot through with colonial assumptions and prejudices. Manuals on Indian medical jurisprudence, framing Indian bodies, customs and “criminal characteristics” as data to be read by European experts. This produced an appearance of objectivity even where analysis reflected cultural prejudice. 

Two pathological patterns flowed from this mixture of science and colonial ideology. Firstly, expert evidence was sometimes used to mask or justify racialised legal outcomes, where medico-legal opinions about “weak constitutions” or “susceptibility” could exculpate European defendants accused of violence against Indians. This dynamic was widely written against in vernacular and English press commentary by the late nineteenth century.

Secondly, experts and laboratories were institutionalised without commensurate standards, peer review or adversarial testing. Kolsky underscores how the colonial search for an “engine of truth” produced a medico-legal machinery grounded in an ethnographic rather than methodologically sceptical scientific framework. 

The codified IEA reflected these pressures. Section 45 recognised expert opinion as a “relevant fact,” institutionalising privilege for persons “specially skilled”, while being reticent about methodological standards or judicial gatekeeping. Such a doctrinal position helped carry forward colonial habits into the post-colonial era. The crucial historical lesson for the BSA is expanding the category of “expert” without requiring Courts and institutions to assess methods and independence risks, repeating the very pathologies that made the IEA problematic.

The Law now: IEA to BSA

The BSA retains the basic structure of admitting expert opinions but introduces an important textual expansion. Section 39, BSA reproduces Section 45, IEA, while adding the phrase, “or any other field,” which changes the closed set of permitted fields to an open-ended category. This change recognises the reality of modern litigation where disciplines such as data sciences, forensic accounting, psychology and econometrics can complement fact-finding. 

Indian precedents confirm that expert evidence is ordinarily treated as relevant but advisory rather than conclusive proof. Courts routinely admit medical, ballistic, fingerprint and DNA reports while insisting that such evidence be tested against primary evidence, cross-examination and other materials on the record. 

The BSA continues the IEA pattern of treating expert opinions as relevant material to be weighed. Still, it does not set out a detailed reliability checklist or impose a pre-admission proof burden comparable to some foreign systems.

Thus, the BSA answers the scope problem while leaving unanswered how judges should assess the reliability of new categories of expert evidence. The statute allows a wider array of opinions, but it does not prescribe how Judges should evaluate methodology, verify credentials, or manage recurring conflicts between clashing opinions. For reform, the decisive question becomes how to convert the BSA’s expanded scope of expertise into reliable fact-finding. 

Potential Pitfalls

The BSA’s broad recognition of experts can be beneficial, but it creates predictable risks if not coupled with safeguards. Firstly, expert shopping and resource inequality can distort outcomes. Wealthier parties and the State can commission multiple experts until one with good credentials supports a desired claim, while under-resourced parties cannot match that capacity. Judges then confront duelling opinions without a clear framework to prefer one over another. 

Secondly, the expansion can entail pseudoscientific or poorly validated techniques to enter litigation. Judges cannot distinguish robust methodology from idiosyncratic assertions without accreditation, peer review, or disclosure of error rates. An apparent example of this was the rush to prematurely use a new, untested technology in criminal investigation and trial in the case of State of Maharashtra v. Sharma.

Thirdly, institutional capture of forensic and analytical laboratories is a serious hazard. Many forensic units remain administratively linked to investigating agencies. If expert evidence is admitted without external audits and independent oversight, laboratory outputs may reflect institutional priorities rather than neutral testing. Ill-defined methods and low standards of chain-of-custody make verification and reproducibility difficult.

Fourthly, judicial capacity and procedural overload limit effective gatekeeping. Vetting difficult techniques takes time, technical expertise and procedural leeway. Overworked benches may admit weak expert evidence by default or exclude reliable but novel methods out of caution.

Finally, unbridled expert authority risks reproducing top-down epistemic patterns. If expert reports are accepted as authoritative without transparent methodology and independent verification, expertise becomes an instrument of power rather than a tool for fact-finding. The historical record warns that expanding expert categories without checks risks repeating earlier pathologies.

Practices in the US & the UK

I. The US

The US Federal system treats expert testimony as a matter of admissibility that requires judicial gatekeeping. Federal Rule of Evidence 702 states that a witness qualified by knowledge, skill, experience, training or education may testify if the expert’s scientific, technical or other specialised knowledge will assist the Court, and if the testimony rests on sufficient facts or data and reliable principles and methods applied reliably to the case.

The modern gatekeeping mandate emerged in Daubert v. Merrell Dow Pharmaceuticals (“Daubert”) in 1993. The Supreme Court held that trial judges must assess whether scientific evidence rests on a reliable foundation before admissibility. The Court provided some non-exhaustive criteria of reliability to be considered by the Courts, including testability, peer review and publication, known or potential error rates, standards and controls, and general acceptance in the relevant community. 

The Supreme Court extended Daubert to non-scientific experts in Kumho Tire Co. v. Carmichael (“Kumho”) in 1999. Kumho confirmed that the reliability inquiry applies to technical and other specialised expertise so that the Judges examine the expert’s qualifications and the method by which conclusions were reached across disciplines.

The Federal Rules of Civil Procedure require detailed expert disclosures and written reports that set out the expert’s opinions, the bases for them, the facts considered and the expert’s qualifications. These disclosures and depositions supply the opposing party and the Court with material necessary to challenge methodology before trial. In practice, many Courts hold pre-trial reliability hearings where Judges evaluate methods on an evidentiary record. Judges may exclude testimony, limit its scope or admit it conditionally.

Institutional support complements such admissibility standards. Accredited laboratories and professional certification provide external indicators of methodological quality. Accreditation schemes such as ISO/IEC 17025 and independent auditing of forensic service providers produce objective markers of competence that Courts and litigants may consult. The availability of neutral experts that the Court may appoint under judicial rules assists in cases where parties have unequal resources.

II. The UK

In the UK, expert testimony is admitted only when it genuinely assists the Court because the matter lies beyond ordinary knowledge. The Supreme Court in Kennedy v. Cordia United Kingdom held that expert evidence must assist the Court, be supplied by a witness with the necessary knowledge or experience, be impartial, and be reinforced by a reliable body of knowledge or methodology. The Court has also warned that a bare ipse dixit opinion without a sound basis is of no value.

A threshold test exists for the admissibility of expert evidence. The test requires inquiring whether the issue requires expert insight and whether such an expert has sufficient skill by study or experience to render their opinion valuable. The English and Welsh Criminal Courts have clarified that novel or unsupported methods must have a sufficiently reliable scientific basis before being admitted.

Procedural rules in civil and criminal trials provide additional safeguards. The Civil Procedure Rules restrict expert evidence to what is reasonably required to resolve the proceedings. Judges may direct experts in the same field to confer and to prepare a joint statement of agreed and disputed matters.

Part 19, Criminal Procedural Rules and the Criminal Practice Directions reaffirm similar duties and criteria for expert witnesses in criminal trials. The Criminal Practice Directions permit expert evidence to enable the Court to access information beyond its own or its jury’s knowledge. They further demand full disclosure of matters that could undermine the expert’s credibility or impartiality.

The UK has also developed an institutional layer that reinforces reliability in forensic work. The Forensic Science Regulator and associated Codes of Practice encourage laboratory accreditation to UKAS and ISO standards, requiring laboratories to observe good practice. Hence, the Courts scrutinise untested hypotheses, unjustified assumptions, and flawed data. These thresholds would serve India’s expert expansion well and can be adapted.

Suggested Reforms

The reforms recommended for India should take the complementary strengths of the US and the UK as their point of departure. Adapting these elements to India requires realistic sequencing and a strong emphasis on the Courts of first instance. In trial Courts, evidence is gathered and contested, and they must be equipped to conduct meaningful and time-efficient reliability assessments. 

Firstly, to address the problem of expert shopping and resource inequality, procedural rules should make methodological transparency and reproducibility the main determinants of admissibility and weight rather than the prominence of credentials. The US model would help require standardised written expert reports that disclose methods, raw data, chain of custody and limitations. The UK model would also help adopt mandatory early disclosures and encourage joint expert statements so that experts can narrow down the disputes. Court-appointed neutral experts for indigent accused and for public interest cases would help ensure that a lack of funds does not preclude meaningful adversarial testing. A central registry of certified experts should be implemented with a modest budget to subsidise independent testing in priority public safety cases. 

Secondly, to prevent pseudoscientific or poorly validated techniques from entering litigation, Courts should require external validation, peer-reviewed evidence of method validity, and published error rates for novel techniques before those techniques are considered decisive. Establishing an accreditation and audit authority that sets minimum ISO style standards would also be prudent while allowing states to operate regional accreditation hubs to increase capacity. Accreditation should be phased and linked to published proficiency testing so that Courts obtain reliable external markers of laboratory quality. A statutory admissibility standard that requires the expert’s methods to be reliable and that the opinion fits the issues would also be a good start. 

Thirdly, to guard against institutional capture of forensic facilities, separate forensic testing institutions from investigative agencies and place them under independent audit and accreditation. The accreditation and audit authority should publish laboratory audit outcomes and enforce chain-of-custody protocols. Also, incentives should be provided for developing regional independent laboratories and cooperation with academic centres so that forensic capacity is distributed and not concentrated within a single agency.

Fourthly, to confront judicial capacity limits and burdens, a national judicial training programme should equip judges with the skills to assess scientific methods and manage expert evidence in day-to-day trials. General practice directions should permit short, time-bound pre-admissibility hearings at the district and Magistrate levels to resolve routine methodological disputes and create precedents in such matters that can be followed. Where complexity and resource imbalance make district-level resolution impracticable, providing a fast track to regional technical benches or to specially constituted panels would help.

Finally, to check the risk of unchecked expert authority, codifying an overriding duty of experts to assist the Court and requiring full disclosures of conflicts of interest, including outcome-dependent fees, would help. Proportionate sanctions for deliberate non-disclosures and positive evidentiary incentives for transparency, such as weight given to experts who supply verifiable data and submit to independent verification, would also help.

This should be done in a phased manner, beginning with diverse district-level jurisdictions. The results can help refine report templates, time limits, and appointment procedures. It would also help calibrate nationwide rules so that the expansion of the definition yields reliable, contestable, and transparent expert evidence at the point where cases are first tried. 

Conclusion

The BSA’s wider statutory definition of experts is necessary for a legal system to adjudicate disputes involving data analysis, technical design and specialised social sciences. Measurable capacity gaps and institutional weaknesses show why safeguards must match statutory expansion. Recent reports indicate substantial backlogs and staffing shortfalls in State Forensic Laboratories, with delays that impede investigations and trials. The National Forensic Sciences University has expanded campuses and programmes, but high-quality practical training remains limited relative to national demand.

The US Daubert/Kumho framework and the UK’s layered approach provide valuable procedural tools, but transplanting these models to India requires decisive adaptation. India has heavy court caseloads, uneven forensic capacity, and limited resources. Therefore, these mechanisms for effective adjudication of expert evidence must synchronise statutory modernisation under the BSA with robust procedural gatekeeping and a rapid expansion of accredited training and laboratory capacity so that expert evidence serves the search for truth rather than merely lending institutional weight.

**Pranav Saraf is a third-year B.A. LLB student at National Academy of Legal Studies and Research (NALSAR), Hyderabad.

**Disclaimer: The views expressed in this blog do not necessarily align with the views of the Vidhi Centre for Legal Policy.