Role of Forensic Science in a Criminal Investigation

This paper attempted to highlight the concept of forensic science with regard to its applicability to the criminal investigation system. It also tries to explore why the role of forensic science is the most requisite part of criminal law. Also, gives special emphasis to the legal provisions associated with a criminal investigation.


Forensic science is the most important aspect of any criminal investigation as it allows the authorities to identify the suspect in crime also helps in determining when and how a crime has occurred. The word ‘forensic’ means “about the law “ so logically forensic science involves the application of scientific principles to legal investigations .thus, forensic science analyzes the evidence received by the police officers and detectives and then make a detailed report of their finding. it helps in identifying the perfect evidence which held the suspect guilty in criminal law.

The subject matters of forensic science are very much vast as it includes various areas, for example, DNA analysis, fingerprint, autopsies, pathology, toxicology, etc., which help in determining the cause of death and the link of the suspect.

Furthermore, Forensic evidence is a discipline that works accordingly with the parameters of the Indian legal system. Its function is to provide direction to those conducting a criminal investigation and to provide the correct information to the judges upon which they can have full trust in determining criminal as well as a civil dispute. In recent times, Forensic science is a highly developed scientific procedure that is used in both criminal and civil investigations. It comprises all prominent scientific techniques such as fingerprint analysis, DNA analysis, ballistics and explosives, firearms, etc.

What is Forensic Science?

The term Forensic Science is defined as “The application of science to those civil and criminal laws that are enforced by the police agencies in a criminal justice system”. More specifically, it answers the questions that are of legal interest and employs techniques and tools to interpret crime scene evidence and use that information in investigations. It deals with the application of the knowledge and methodology of various disciplines of science to legal matters. It involves the use of multiple disciplines such as physics, chemistry, biology, computer science, and engineering for evidence analysis. For instance, physics is used to understand the pattern of a blood spatter, biology to establish the source of an unidentified suspect and chemistry to determine the composition of drugs. Therefore, the application of forensic science in criminal investigation and the legal system is often underestimated and extremely critical.

For evidence analysis, it includes the use of multiple disciplines such as medicine, biology, forensic chemistry physics, DNA profiling, and computer science.

History and Origin

The concept of forensic science is not new in the criminal investigation system. It dates back thousands of years. Argentina was the first country to incorporate forensic evidence for a criminal investigation in 1902. Sir William Herschel was one of the first to advocate the use of fingerprinting in the identification of criminal suspects. By the late 1700s, forensic science was being used as a factor to determine guilt or innocence in major criminal cases, including murder charges. One of the primary functions of forensic science is to study DNA, the genetic coding found on all living things.  By the end of the 20th century, forensic scientists had a plethora of high technology tools for analyzing evidence from DNA analysis to digital fingerprinting techniques with computer search capabilities.

Types of Evidence

There is a variety of forensic evidence collected at crime scenes; for example -fingerprints, impression evidence, hair, fiber, firearms, biological evidence, drug evidence, and entomological evidence, etc.

  • Fingerprint Evidence: Fingerprint evidence is used to determine if someone is connected to the crime or a  part of the crime scene. It also helps the investigator to track the record of the criminal’s previous arrest or conviction.
  • Trace Evidence: Trace evidence is a general term for small, sometimesmicroscopic, material. It covers such small evidence like fibers, hair,dust, building materials that it can be transferred without being noticed.
  • DNA /Biological Evidence: The two most common types of biological evidence are saliva and blood. Blood evidence comes in the form of wet blood (e.g., a tube of blood from an autopsy) or swabs of bloodstains collected at crime scenes. Other types of biological evidence include hair, seminal stains, urine, and perspiration. In each case, the motive is to provide sufficient samples of biological evidence to allow DNA profiling.
  • Weapons Evidence: It consists of firearms (  handguns, rifles, assault weapons, etc.), ammunition (e.g., spent casings, fired projectiles, bullet fragments, and unfired bullets), gunshot residue (GSR) tests, and knives. The purpose of a GSR kit is to determine whether an individual was close to a firearm at the time of discharge.
  • Drug Evidence: Drug evidence includes drugs (e.g., marijuana, cocaine, methamphetamine, and others), and drug paraphernalia (pipes, spoons, etc.) found at a scene.
  • Natural/Synthetic Materials: Natural and synthetic materials include clothing, bed and bath material, carpet cuttings, plastic, paper, and metal objects.
  • Generic Objects: Generic objects include vehicles, bicycles, containers, doors, wood, and concrete.
  • Digital evidence: It involves the evidence found in computers and digital storage media like pen drives, hard disks, etc. Its major objective is identifying, preserving, recovering, analyzing, and presenting facts and opinions about digital information.
  • Other Items: Other items are a catchall category for evidence that does not fit in any of the above categories.

A key element of Forensic Investigation

  1. Crime Scene–  A scene of occurrence of a crime is a place where a particular crime has been committed or where physical evidence of such crime has been found when it is first conducted to the notice of the police.  It is a starting point for the investigator, which provides him with the information on the victim and the suspect, and to reconstruct the crime.

The scene of occurrence cannot be limited to one place only. It may extend to one or more places. It may also not be limited to immediate surroundings, but may In a wider area depending upon the nature of the crime committed. In a compact scene of the crime, such  as burglary, the scene may be divided into five parts, namely:

  • Line of approach
  • Point of entry;
  • Actual scene;
  • Point of exit; and
  • Line of retreat.
  • Preservation of the Crime Scene – Preservation of the crime scene is the most important task of the police officers. There is a duty of the first person arriving at the scene to protect the scene from curious onlookers and family members. Nothing on the scene should be changed. touched or altered until the investigating officer takes its proper note. Once any material object of a dead body is moved from its place, it can never be restored to its original position That scene, once touched or altered, will make the task very difficult for an investigator.
  • Recording of the Crime Scene – After taking immediate action to preserve the crime scene, the Investigator should then proceed to record the evidence. he should seek the help of two reliable witnesses, preferably from the neighborhood of the crime scene, as their presence will strengthen the case of prosecution at the time of trial. No evidence should be picked up, or touched or even disturbed till every minute details have been described in a notebook.

Recording of the crime scene including

  • Recording of notes
  • Sketching the crime scene
  • Photography of the crime scene

Role and Application of FS in a criminal investigation

Forensic science is the key element in a criminal investigation without which the investigation is not complete. It has a remarkable contribution in solving criminal investigation and other heinous violence. Without the forensic science application, criminals can never be convicted unless an eyewitness is present. After the commencement of the crime, police and other law enforcement agencies are involved in the collection of evidence, the investigating officer tries to collect the maximum evidence found at the site of the crime be it physical or digital because a minuscule proof can revert the case. And it is forensic science that deals with the analysis of those evidence to establish the facts admissible in the court of law. Thus without the help of forensic science, murderers, thieves, drug traffickers and rapists would be roaming scot-free.

Forensic science plays a crucial role in the criminal justice system as it provides the scientific-based information through the analysis of physical evidence, the identity of the culprit through personal clues that associate with the criminal through objects left by him at the criminal site like a fingerprint, blood drop or hair, footprints, mobile phones or any other gadgets.

When it comes to forensic science, there is a great role of scientists who deals with it. The duties and responsibilities of a forensic scientist in a criminal investigation is critical as it involves the careful examination of evidence while ensuring that it is not tampered with. Forensic science involves forensic tools in the investigation of a criminal act.

For instance, forensic pathologists are skilled at determining the cause of death by performing autopsies. An autopsy helps establish the cause and manner of death through the examination of body fluids and tissues. Forensic Scientists analyze physical evidence like fingerprints, blood, hair, etc. collected from the incident scene to identify suspects. Furthermore, forensic professionals use image modification tools to search for criminals absconding from the law for a long time. This tool allows them to digitally age a photograph to understand how the individual would look at aging.

Legal Provisions Supporting Criminal Investigation

The evidence found at the crime scenes provides the investigating officer a splendid piece of information with the help of scientific technology. They help the court to find out the answers to certain questions like how the crime has been committed? What is the nature of the crime? Who are possible suspects? And by answering all these questions they try to recreate the crime and then try to find out the reason for the commission of the crime, thereby reaching out to the criminal.

Though forensic science has made a remarkable contribution to the criminal justice system, the limitation of law is inevitable. Some predominant questions revolved around the mind of many legal professionals viz;

  • How far are these techniques legitimate?
  • How forensic evidence be admissible in the court of law?
  • How this evidence be helpful in a criminal investigation?

There have been many debates and discussions that forensic evidence presented in the court of law defeats the basic provision of law.

  1. As per Articles 20(3) of the Indian Constitution, no person accused of any offense shall be compelled to be a witness against himself. This article defends the accused from the mental harassment they undergo during detention. Criminal law believes an accused is innocent until his guilt is proved beyond a reasonable doubt.
  2. Many people argued over a debate that fingerprints and DNA analysis for verification defeat the provision of Art. 20(3). They felt that forcing the accused to give fingerprints is like the accused giving evidence against themselves. But the Supreme Court in the case of the State of Bombay v. Kathi Kalu Oghad and Anr[1] held that compelling any person to give any sort of forensic evidence like fingerprints, blood, hair semen, does not violate the provision of Art. 20(3)
  3. The same is even mentioned in Sec. 73 of the Indian Evidence Act, which directs any person including the accused can be asked to give the fingerprint or DNA examination.
  4. Another debate was on Narco-analysis and its constitutional validity. Narco-analysis is new in the field of the criminal investigation. But the question arises whether the evidence by narco-analysis admissible in the court of law?. In this method, the investigating officer tries to acquire some sort of statements from a semi-conscious person which can be used as the evidence.  This process possesses several questions about law and ethics. Some felt that it is violating the provision of Art. 20 of the Indian Constitution against self-incrimination. 
  5. The Bombay high court in  Ramchandra Reddy and Ors. v.The state of Maharashtra upheld the legality of the use of lie detector tests and the use of narco analysis. But in the case of Selvi and Ors. v. State of Karnataka and Anr. The court held that the person giving statements in brain mapping or narco-analysis tests is inconclusive and thus their compulsory investigation would be unconstitutional.
  6. Section 53 of the Criminal Procedure Code, 1976, provides that a person accused may be subjected to a medical examination if the officers believe that the examination can provide some evidence to the crime.
  7. In 2005, certain amendments were made in Criminal Procedure to include the examination of blood-stain, DNA profiling, semen test, swabs, hair samples, etc., but it was constrictive only to the rape cases.
  8. In a similar way Sec. 164A of Criminal Procedure also authorizes the medical examiner to examine the victim of the rape case within 24-hours. But the question arises whether all the practitioner is proficient for the collection of DNA samples. It is a well-known fact that the sample collection must not be contaminated as it would be of no further use

Thus, the criminal justice system has an immense belief in forensic science and has depended on them since ages for delivering judgment. Forensic reports are considered as the bible for many judges and have been regarded as belief tendered by experts. But courts are not bound by the reports and can count on other evidence


It can be evaluated that Forensic science plays an integral role in the criminal justice system. Some well-trained forensic scientists are trained to analyze crime scenes, evidence, and personal testimony to create a visualization of how a crime occurred. In modern times, there has been an increased rate of crimes, so that the technique of the crime has also changed and advanced as per the technology. Therefore it is pertinent that the police and the investigating machinery use forensic science to detect crime and also are at par with the growing technology and various natures of crime.  Forensic science can be used in almost every criminal case; however, investigations of rape, homicide, and burglary are those that benefit the most from forensic science. The main aim of the criminal justice system is to provide fair justice. Doubtlessly, forensic evidence is more authentic than ocular evidence. Forensic science being scientific evidence is a prerequisite for the criminal justice system.


  1. What are the roles of forensic science in the criminal justice system?
  2. What are the laws supporting criminal investigation?
  3. How does the forensic evidence will admissible in a court of law?


  • [1]Bombay v. Kathi Kalu Oghad and Anr. AIR 1961 SC 1808, 1962 SCR (3) 10
  • [2] Ramchandra Reddy and Ors. v. The state of Maharashtra. 2004 ALL MR (Cri) 1704
  • [3]Selvi and Ors. v. State of Karnataka and Anr. AIR 2010 SC 1974

Leave a Reply

Your email address will not be published. Required fields are marked *