Introduction to Forensic Science: Importance of Forensic Science in Law

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Forensic Science

Forensic Science

  • The word forensic comes from the Latin adjective forensic, meaning “of or before the forum.” In Roman times, a criminal charge meant presenting the case before a group of public individuals in the forum.
  • Forensic science is the application of science to criminal and civil laws during criminal investigations, as governed by legal standards of admissible evidence and criminal procedure.


Importance of History

Importance of Forensic Science in Law

  • The word “forensic” has its roots in the Latin word “foresees” which means a forum.
  • Back in early Rome, a forum referred to a public place where judicial proceedings and debates were held.
  • Thus, the origin and the very definition of ‘forensic science’ points to its close association with the legal system.
  • Forensic Science involves the collection, preservation, and analysis of evidence suitable for prosecuting an offender in the court of law.
  • The application of forensic science in the criminal justice system is, therefore, an apparent picture.

Basic Principles of Forensic Science

  • Law of Individuality
  • Principle of Exchange
  • Law of Progressive change
  • Principle of Comparison
  • Principle of Analysis
  • Law of Probability
  • Facts do not Lie

Law of Individuality

  • Every object, natural or man-made, has an individuality, which is not duplicated in any other object. It is unique. Neither the nature has duplicated itself, nor man can.
  • It is due to small flaws in the materials, in the arrangement of crystals, imperfect of some or due to inclusion or exclusion of some extraneous matter or other material.
  • To identify the uniqueness to link the crime with the criminal.
Law of Individuality

Principle of Exchange

  • Whenever two entities come in contact, there is an exchange of traces mutually. ′ It is also known as Lockard ′ s principle.
  • The change in some cases is very small and undetectable but in some other cases it is detectable by scientific methods.
  • On a thorough search traces connect the crime and the criminal as effectively.

Law of Progressive Change

  • Everything changes with the time.
  • Longer the delay in examining the scene, greater will be the change.
  • The degree of change depends upon the time, the upkeep and the extent and frequency of use or misuse of the particular object.

Principle of Comparison

  • Only the likes can be compared.
  • It emphasizes the necessity of providing like samples and specimens for comparison with the questioned items.

Principle of Analysis

  • The analysis can be no better than the sample analyzed.
  • The principle emphasizes the necessity of correct sampling and correct packing for effective use by experts.
  • Improper sampling and contamination render the best analysis useless.

Law of Probability

  • It determines the chances of occurrence of a particular event in a particular way out of a number of ways in which the event can take place or fail to take place with equal facility.
  • All identification definite or indefinite made consciously or unconsciously on the basis of probability.

Facts Do Not Lie

  • Facts do not lie , men can and do ′ .
  • Also called as “Law of circumstantial facts” .
  • Oral evidence is colored as modified by auto suggestion, external influence, suggestions, descriptions and opinions of others and rationalization.
  • The two basic principles that constitute the pillars of forensic science have been attributed to Paul L Kirk and Edmond Lockard.
  • Indeed, Kirk՚s principle can easily fit the forensics model, while Lockard՚s principle provides opportunities for an extension of this model.
Edmud Lockard and Paul L Kirk


  • Forensic science certainly is very important field.
  • The need of forensic science is directly related to number of criminal cases.
  • Judiciary requires certain scientific facts i.e.. examination of evidences to help them in giving justice.
  • So, these scientific examination of various evidences is done by forensic scientists only.
  • And they are called in the court as an scientific expert.