BIOMETRICS IN CRIMINALISTICS AND SCIENTIFIC INVESTIGATION
AUTHOR – G R RADHIKA, STUDENT AT THE TAMILNADU DR.AMBEDKAR LAW UNIVERSITY SCHOOL OF EXCELLENCE IN LAW
BEST CITATION – G R RADHIKA, BIOMETRICS IN CRIMINALISTICS AND SCIENTIFIC INVESTIGATION, INDIAN JOURNAL OF LEGAL REVIEW (IJLR), 6 (9) OF 2026, PG. 531-545, APIS – 3920 – 0001 & ISSN – 2583-2344.
I. INTRODUCTION
Criminalistics—the scientific examination of physical evidence for use in criminal proceedings—has been transformed more dramatically in the past three decades than in any comparable period since Locard articulated the principle that every contact leaves a trace.[1] At the centre of that transformation is biometric technology: systems that capture, store, and analyse the unique physical and behavioural characteristics of human beings for the purpose of identification. Fingerprints, DNA profiles, iris patterns, facial geometry, voice signatures—each of these has moved from specialist laboratory technique to routine investigative tool, deployed across Indian police stations, forensic science laboratories, border checkpoints, and courtrooms.
The scale of this deployment is worth pausing over. India operates the world’s largest biometric identity database through Aadhaar, which has enrolled over 1.3 billion people.[2] The National Crime Records Bureau maintains a growing database of fingerprint, DNA, and increasingly facial recognition records linked to criminal proceedings.[3] The Criminal Procedure (Identification) Act, 2022 has expanded what the state can collect, from whom, and for how long—replacing a 1920 law that covered only fingerprints and footprints with one that reaches to iris scans, blood samples, and behavioural measurements.[4] And the three new criminal law statutes—the Bharatiya Nyaya Sanhita (BNS), the Bharatiya Nagarik Suraksha Sanhita (BNSS), and the Bharatiya Sakshya Adhiniyam (BSA)—have rewritten the procedural and evidentiary framework within which all of this data is collected, processed, and placed before courts.[5]
The legal and policy questions this raises are not peripheral concerns for specialists. They go to the heart of how India balances the legitimate demands of effective crime investigation against the constitutional rights of everyone who comes into contact with the system. The Supreme Court settled the constitutional baseline in Justice K.S. Puttaswamy v. Union of India,[6] establishing privacy as a fundamental right under Article 21. But constitutional principles, however clearly stated, do not enforce themselves. The question is whether the statutes, rules, and institutional arrangements that govern biometrics in Indian criminal justice are actually adequate to the task.
This paper makes the case that they are not—at least not yet. The scientific and investigative power of biometric technology is real, and its contribution to criminal justice is substantial. But the legal framework has consistently lagged behind the technology it is meant to govern, and the gaps that have opened up carry serious consequences for privacy, due process, and the rights of marginalised communities. The paper works through the science, the law, and the policy in sequence, with a view to identifying precisely where reform is most urgently needed.
[1]Locard, Edmond, “L’analyse des poussières en criminalistique,” Revue Internationale de Criminalistique (1929); see generally Paul L. Kirk, Crime Investigation: Physical Evidence and the Police Laboratory (1953).
[2]Unique Identification Authority of India, Annual Report 2022–23 (2023).
[3]National Crime Records Bureau, Crime in India Report 2022 (Ministry of Home Affairs 2023).
[4]Criminal Procedure (Identification) Act, No. 11 of 2022 (India).
[5]Bharatiya Nagarik Suraksha Sanhita, No. 46 of 2023 (India).
[6]K.S. Puttaswamy v. Union of India, (2017) 10 SCC 1 (India).