CRITICAL ANALYSIS OF ROLE OF FORENSIC SCIENCE IN INVESTIGATION OF SEXUAL OFFENCE

AUTHOR – V.BHAVYAA NACHIAR* & MR. SUGITH KUMAR**

* STUDENT, SCHOOL OF EXCELLENCE IN LAW TNDALU

** ASSISTANT PROFESSOR AT SCHOOL OF EXCELLENCE IN LAW TNDALU

BEST CITATION – V.BHAVYAA NACHIAR & MR. SUGITH KUMAR, CRITICAL ANALYSIS OF ROLE OF FORENSIC SCIENCE IN INVESTIGATION OF SEXUAL OFFENCE, INDIAN JOURNAL OF LEGAL REVIEW (IJLR), 6 (2) OF 2026, PG. 130-139, APIS – 3920 – 0001 & ISSN – 2583-2344.

ABSTRACT

This research paper critically analyzes the role of forensic science in investigating sexual offenses, focusing on rape cases, by contrasting its theoretical potential with empirical limitations. Sexual offenses pose a profound global challenge, with millions of reported incidents yearly yet conviction rates languishing at 23-28% in regions like India, largely due to evidentiary shortcomings and high attrition rates. Forensic science provides indispensable objective evidence, including biological samples (semen, DNA from vaginal/anal/oral swabs via STR and Y-STR profiling, saliva), trace materials (hairs, fibers, toxicology for drug-facilitated assaults), and injury patterns (genital trauma, bruising, petechiae).nij.ojp+1

The study delineates forensic protocols: Sexual Assault Evidence Collection Kits (SAECK) administered by trained Sexual Assault Nurse Examiners (SANE) within 72-96 hours to preserve fleeting biological traces against degradation from victim hygiene or delays. It covers investigation phases—victim medical exams, crime scene processing, chain-of-custody lab analyses (PCR amplification), and non-DNA integration, where injuries alone can increase arrest odds fourfold. Empirical insights from the National Institute of Justice’s 602-case study reveal DNA yields of 37-47%, but real-world barriers like untested kit backlogs (over 100,000 in the U.S.), contamination, and interpretive biases erode prosecutorial impact.cfrc.illinois+1

Case analyses highlight successes, such as familial DNA matches in cold cases, contrasted with failures from post-assault showers dropping recovery below 20%. Regional disparities, especially in resource-poor settings, amplify challenges like lab overloads and victim reluctance. The paper employs outcome tables to compare DNA versus non-DNA evidentiary value across victim demographics and offense types.

It advocates reforms: enhanced SANE training, rapid DNA tech, backlog clearance funding, and victim-centered policies fusing forensics with judicial processes. Forensic science, thus positioned as a justice catalyst, demands systemic evolution to fulfill its promise against sexual violence.

Keywords: Forensic science, sexual offenses, rape investigations, DNA profiling, Y-STR, SANE protocols, evidentiary attrition, conviction rates, chain-of-custody, non-DNA evidence, toxicology, crime scene forensics.