Written By: Ms. Priyanka Patne
M.Sc. Forensic Science, Oriental University, Indore, patnepragya3@gmail.com
Abstract
This case study focuses on the 2012 Delhi gang rape and murder case, widely known as the
Nirbhaya case, which triggered significant changes in India’s approach to crimes against women.
The victim, Jyoti Singh, a 22-year-old physiotherapy intern, was brutally attacked by six men on
a moving bus in Delhi. The attackers gang-raped, tortured, and physically assaulted her and her
male companion before throwing them out of the bus. She sustained severe injuries, including
damage caused by a rusted metal rod, and despite medical efforts, she died days later in a Singapore
hospital.
The case stirred nationwide outrage, leading to major public protests demanding justice and
reforms in the laws related to sexual violence. It highlighted critical deficiencies in the legal and
policing systems and sparked the creation of stricter laws and faster judicial processes for crimes
against women.
The investigation resulted in the arrest and trial of the accused, including adults and one juvenile.
The four adult convicts were sentenced to death after being found guilty of rape and murder in a
fast-track court, while the juvenile received the maximum sentence allowed by law. The convicted
men were executed in 2020, marking a decisive moment in India’s legal response to such crimes.
This case study emphasizes not only the horrific nature of the crime but also its role in changing
Indian society's awareness and legal framework regarding women's safety. It also underlines the
importance of swift and fair judicial action as a deterrent to such offenses. The Nirbhaya case
remains a landmark precedent for victim justice and gender violence laws in India, showing how
a single incident can ignite widespread social and legal transformations.
Introduction
“Bite marks” — the patterned injury left by the teeth of one person on the body of another —
represent a specialised form of forensic dental evidence. In forensic odontology, bite-mark analysis
seeks to link the dental characteristics of a suspect to the injury pattern observed on a victim (or
sometimes on the assailant). Research has noted that human dentition is unique in its arrangement,
shape, and individual characteristics, and hence, in theory, bite-marks may provide a means of
identification. However, the analysis is challenging: skin is a dynamic medium, injuries undergo
healing, distortion may occur, and the uniqueness of bite marks as forensic marks has been a
subject of debate.
In the context of the 2012 Delhi gang-rape and murder case, commonly referred to as the
“Nirbhaya” case, bite-mark evidence played a notable role among multiple lines of scientific
evidence. The victim sustained multiple injuries including bite-marks, which were subsequently
examined and compared to dental models of the accused. This report explores the bite-mark
evidence in the case: how it was used, what findings emerged, why it is significant in the forensic
and legal context, and what conclusions we can draw.
Findings (Nirbhaya Case)
Case name- nirbhaya case (new delhi)
Case investigate -IPS chhaya sharma
Date- december 16, 2012
Time- 20:30
Location - munirka (new delhi)
Victims - Jyoti Singh,awindra pratap panday
Culprits -Akshay thakur,mukesh singh,md.afroz, Pawan Gupta, Ram Singh, Vinay Sharma
In the Nirbhaya case (16 December 2012, Delhi), the victim was brutally assaulted, gang-raped
and ultimately died of her injuries. Among the forensic evidence collected were bite marks on the
victim’s body. According to the Supreme Court judgment and forensic reports:
Forensic odontology examination -
• The forensic odontology examination compared the bite-marks on photographs of the
victim’s body with dental casts (models) of the accused.
• The Supreme Court observed: “at least three bite marks were caused by accused Ram Singh,
whereas one bite mark has been identified to have been most likely caused by accused
Akshay.”
• The Court noted that the report was “wholly credible” because of the matching of bitemarks with the tooth structure of the convicts, and that there was no reason to view the
odontological evidence with suspicion.
• Additional factual detail: The forensic odontology department at the SDM Dental College,
Dharwad received photographs of the bite-marks and dental models of the accused from
the Delhi Police. They took about five days (January 3–7, 2013) to conduct analysis and
submitted a detailed 12-page report that at least two accused’s dental models matched five
bite-marks.
• The Supreme Court in May 2017 explicitly said that scientific evidence including bitemark analysis sealed the fate of the four adult convicts.
Detail of how analysis was done
While the publicly available information does not present the full report, certain methodological
aspects are described:
• Photographs of the bite-marks (on the victim’s body) and dental models/impressions of the
accused.
• Use of computer-based 2D digital analysis to compare the patterns.
• Matching of “concordant points” (i.e., distinctive corresponding landmarks) such as tooth
edges, cusp patterns, spacing of teeth, orientation of incisors, rotations, etc. For example,
one bite-mark matched the rotated left first incisor of accused Akshay.
• The report concluded with “reasonable medical certainty” that the bite marks were caused
by the teeth on the dental models of the accused in question.
Challenges or considerations
The Supreme Court itself acknowledged that unlike fingerprints or DNA, bite-marks “lack the
specificity and durability” because human teeth may change over time and skin may distort.
Nevertheless, the Court held it was reliable in this case given the circumstances.
The situation in this case was aided by the high degree of brutality, large number of marks, rapid
response in preserving evidence, and quality of forensic work.
So, summarising: in the Nirbhaya case, the bite-mark evidence acted as supportive corroboration
alongside other scientific evidence (DNA, fingerprints) and helped the prosecution in linking
specific accused (Ram Singh and Akshay Kumar Singh) to the crime via forensic odontology.
Importance / Significance
The use of bite-mark evidence in the Nirbhaya case illustrates several important aspects in forensic
investigation and criminal justice:
1. Corroborative scientific evidence
The case demonstrates how bite-mark analysis can serve as one component of a larger forensic
strategy: it was not the sole evidence, but helped strengthen the chain linking accused to the victim
and the crime scene. The Supreme Court explicitly noted that “scientific and forensic evidence
like DNA, fingerprints and bite marks analysis” sealed the convicts’ fate.
2. Forensic odontology’s role in sexual assault and violence cases
In violent assaults (particularly sexual assaults), perpetrators may bite the victim as an expression
of dominance, rage or control. The presence of bite-marks may thus carry significant forensic value.
In India, the Nirbhaya case is often cited as a reference point where odontology contributed
meaningfully in a high-profile trial.
3. Strengthening investigation in complex crime scenes
The crime took place in a moving bus, with multiple perpetrators, massive injuries, and attempts
at evidence destruction (bus floor changed, etc.). The efficient use of forensic tools (including bitemark comparison) underlined how modern investigation can adapt to complex, brutal crime scenes.
4. Legal and precedential significance
The Supreme Court’s acceptance of the bite-mark analysis as “wholly credible” provides a strong
jurisprudential precedent in India for acceptance of forensic odontology in criminal trials.
The case can act as a model for other courts dealing with sexual offences and incorporates scientific
evidence as standard practice.
5. Highlighting limitations and need for proper methodology
The court’s acknowledgement of limitations (lack of specificity/durability compared to
DNA/fingerprints) is important. It reinforces that bite-mark evidence must be handled with
rigorous methodology, proper documentation, chain of custody, expert evaluation, and
corroboration with other evidence.
Sexual assault and violent crime investigations need timely evidence collection (bite marks
heal/blur), photographic documentation, and standardised protocols. Articles on bite-mark analysis
emphasise this.
Thus, the significance of bite-mark evidence in this case is both forensic (adding a piece of link
evidence) and symbolic (reflecting advancement of investigative practice in India).
Conclusion
The Nirbhaya case stands as a landmark in Indian criminal jurisprudence not only for its immense
social and legal implications but also for demonstrating the evolving role of scientific forensics.
The bite-mark analysis, undertaken by forensic odontology experts and accepted by the Supreme
Court, served as a key corroborative link tying two of the accused with the victim’s injuries.
Although bite-mark analysis has known challenges — such as potential distortion of skin, changes
in dentition over time, and less long-term reliability compared to DNA or fingerprints — in this
case it was conducted under strong procedural discipline and in conjunction with other forensic
evidence, thereby enhancing its credibility.
For students of forensic science, criminology and law, this case highlights several lessons: the
importance of multidisciplinary forensic support, the value of timely and methodical evidence
collection, the need for documented chain of custody, and the significance of expert testimony in
odontology. It also underlines that forensic tools are not infallible in isolation; rather, they gain
strength when integrated with circumstantial evidence, witness testimony, scene reconstruction
and other forensic modalities.
In short, the bite-marks in the Nirbhaya case illustrate what proper forensic odontology can
accomplish in the Indian criminal justice system: bridging the gap between violent physical
evidence and actionable legal outcomes. For future cases of sexual assault and violence, this
reinforces best practices — from rapid injury documentation to expert comparison of dental
models, to court-ready documentation of methodology and findings. Ultimately, the case
reinforces the simple principle: meticulous forensic work can help turn raw crime into successful
prosecution, supporting the goal of justice for victims.
Reference
1. https://en.wikipedia.org/wiki/2012_Delhi_gang_rape_and_murder
2. https://www.bbc.com/news/world-asia-india-59360488
3. https://indianexpress.com/article/explained/what-is-nirbhaya-case-women-safety-laws-inindia-7111539/
4. https://www.scobserver.in/judgments/mukesh-v-state-for-nct-delhi-2017/
5. https://open.library.ubc.ca/cIRcle/collections/ubctheses/24/items/1.0346168
