Forensic Science and its 9 Governing Principles via The Legal Conundrum

The word ‘forensic’ is derived from the Latin word ‘forensis’ that relates to a discussion or examination performed in public. Forensic science is the application of science and the scientific method to matters of law and resolution of legal conflicts. It is a multi-disciplinary subject which draws upon physics, chemistry, biology, computer science and other scientific principles and methods and is concerned with the recognition, identification, individualisation, and evaluation of physical evidence.

As society moves towards more scientific response to solving crime, significant advances have been made in the fields of serology, fingerprint and footprint analysis, handwriting analysis, ballistics and toxicology among others. Forensic scientists study and interpret the different types of evidence found at a crime scene. They employ techniques and tools for recovery and collection of crime scene evidence, so as to ensure that criminal evidence is recovered and retained without being contaminated and altered, packed and sent in a scientific and safe manner to the laboratory where the latest techniques are deployed and applied to extract prosecutable evidence that will link the evidence to the scene of crime and finally to the criminal so that he or she may be successfully prosecuted. Forensic scientists not only analyse and interpret evidence but also provide expert witness testimony in the Courts.

Forensic science has developed its own laws and principles. They guide the disciplines and methodologies of science in analysing the evidence impacting the proceedings in the Court of law. The following laws and principles are essential in crime scene investigation to link a suspect to the victim and the crime scene.

1. Locard’s Exchange Principle

Edmund Locard (1877-1966)
Edmund Locard (1877-1966)

Edmund Locard (1877-1966), a French scientist postulated the exchange principle in 1928 which asserts that every contact leaves a trace.

According to Locard, when a person or his instruments comes into contact with another person or object, a cross transfer of materials occur. They leave trace, and likewise pick up traces from the same contact. Such transfer or exchange may be large or small, visible or invisible, readily detectable or difficult to detect. It is the responsibility of the Investigating Officers to search, identify and collect such evidences.

Thus, a mutual exchange of traces takes place between the criminal, the victim and the objects involved in the crime. Every criminal can be linked to a crime by dust particles carried from the crime scene. For instance, in a case involving counterfeit coins, Locard asked the police to bring the three suspect’s clothing to his lab. After examination he recovered small metallic particles from the cloth material which made up the composition of the coins. Confronted with this evidence, the suspects were arrested and soon confessed to the crime.

2. Principle of Evidence Recovery

The principle of evidence recovery provides that no harm should be done to the evidence. Nothing should be added, lost, damaged or obliterated in the recovery process.

Careful attention should be taken to avoid contamination. Great care should be taken when there is a risk of losing or damaging evidence. Exhibit items need to be safely and securely packaged and transported to the laboratory.

3. Law of Individuality

Paul L. Kirk (1902-1970)
Paul L. Kirk (1902-1970)

Law of individuality is attributed to Paul L. Kirk (1902-1970) and provides that two objects may be indistinguishable; however no two objects are identical.

Individuality implies that every entity, whether person or object, can only be identical to itself and so is unique. It expresses that all articles or objects, man-made or natural, possess an individual character which under no circumstances is duplicated. Everything involved in a crime has an individuality which when established connects the crime to the criminal. The reasons for this could be either minor flaw present in the raw material, or imperfect stamping or variation in configuration of the crystals or substitution of some quantity of extraneous matter.

4. Law of Progressive Change

Law of progressive change provides that everything changes with the passage of time.

Change is inevitable. Different types of objects may take different time spans. Sample degrade with time, bodies decompose, firearm barrel loosen, tire tracks fade, metal objects rust. The scene of occurrence undergoes rapid changes.

5. Principle of Comparison

Principle of comparison asserts that only the likes can be compared. It emphasises the need of providing like samples and specimen for comparisons with the questioned items. A questioned hair can only be compared to another hair sample, likewise with blood samples, bite marks, tire marks, tool marks, etc.

Two objects are said to match when there are no unexplained, forensically significant differences between them.

If a comparison is conducted as the final and ultimate test, the rule is if in doubt, exclude. Whereas, if the comparison is conducted as a screening prior to the other tests, the rule is if in doubt, include.

6. Principle of Analysis

The principle of analysis stresses on the need of correct sampling and correct packing for effective use by experts. The quality of any analysis is determined by the quality of the sample under analysis, the chain of custody, and the expertise of the individual who analyses it.

The analysis can be no better than the sample analysed. Improper sampling and contamination render the best analysis useless.

7. Principle of Presentation

The principle of presentation provides that the laboratory report should be readily understandable and impartial. It should neither be understated, not overstated.

Complete disclosure should be made of all facts, assumptions, data, conclusions and interpretations.

8. Law of Probability

The law of probability asserts that all identification, definite or indefinite, is made, consciously or unconsciously, on the basis of probability.

Probability determines the chances of occurrence of a particular event in a particular way.

9. Law of Circumstantial Facts

The law of circumstantial facts has its basis in ‘facts do not lie, men can and do’.

The oral testimony depends upon the power of observation, assimilation and reproduction of the witness. It may be disturbed by rationality, external influence, suggestions, descriptions and opinions of others. Whereas factual evidence is free from these infirmities.

Thus, evidences given by victims or eye witnesses may not always be accurate. Sometimes they may intentionally lie or make up facts, or exaggerate or make assumptions or give evidence while having to rely on their poor senses.  On the other hand, evidence which gives a factual account e.g. based on investigation and evidence has a higher chance of being accurate and is more reliable.

The word ‘forensic’ is derived from the Latin word ‘forensis’ that relates to a discussion or examination performed in public. Forensic science is the application of science and the scientific method to matters of law and resolution of legal conflicts. It is a multi-disciplinary subject which draws upon physics, chemistry, biology, computer science and other […]

Forensic Science and its Governing Principles and Laws — The Legal Conundrum

Forensic Expert via The Forensic Science Public Desk, India

Who is an Expert?

I am an expert in doing sketches. How? I am passionate about sketching and drawing since my childhood and still, I practice it. I take a very short time to do any kind of sketch within few minutes compared to the capability of any other common human. Hence, It can be said as he has expertise in the art of sketching and he has knowledge on sketching where he can form an opinion or comment on other work whether it is authentic, truly hard work, commendable work or possibilities and what were the possible ingredients used to make a certain sketch.

So that was an example which gives us a better understanding of who is an expert.

A person who has special knowledge and skill in a particular branch of learning and thus qualified to give his opinion, whereas, an ordinary person is not competent to do so.

Thus, Doctors, artists, engineers, surveyors, engravers, mechanics, artisans, and the diverse classes of specifically skilled workmen would all be experts within the meaning of the expert, of course, each in his walk of life.

How can you be one? 

Crimes are associated with the number of evidence like blood, bullet or a dead body. Identification or classifying any of this would easy due to definite science which is available as the experience of individuals working with a field like serologists, Ballistic experts or Doctors. This particular aspect can be learnt and it can apply to

Section 45 in The Indian Evidence Act, 1872

Opinions of experts.—When the Court has to form an opinion upon a point of foreign law or science or art.

What is foreign law or science or art? Means, Court is represented by personnel’s dealing with law and justice enforced for public welfare. I pursuit of justice there are certain aspects which are also involved like science. Representatives of court, that is judges or law Practitioners are not aware of these particular sciences like serology or physics or medicine nor they can complete the degree in few days nor they can be unethical by justifying anything on their own. They are knowledgeable personnel’s in enacting law and justice for public welfare but not to justify truth hidden within the scientific evidence like nature of injury on the body or striation marks on the bullet.

Hence, the Court needs to rely on expert opinion to understand the significant scientific evidence role of any kind of case dealt with in the court.

Examples

Doctor: As to ascertain the cause of death or time since death

Chemical examiner: identification of a questioned substance by conducting chemical examination which approved by scientific statutory bodies.

Ballistics expert: identification of alleged firearm by comparing test-fired bullet and questioned bullet.

Court believes science-based literature, research held and scientific principles or laws developed during a search of the reality behind happenings of many unknown things to mankind.

Whom will you handover the evidence to?

Just imagine if you are having an Evidence which is a “Document with disputed signature, questioned age of ink in the signature and contents on the questioned document” Whom will you handover the evidence to?

One who has just completed Masters in Forensic Science – has experience practice with demo samples or simulated samples or experience while in internship or project under the supervision of an expert. The court cannot rely on you leaving behind qualified experts but you should be having the capability to convince the court in the science subject matter thus makes you an expert. Anybody one who can prove or involve in the scientific examination of the evidence on the grounds of being intellectual in scientific principles and law which are in current practice by many of the recognized scientists can be referred and can be used to prove the truth hidden with evidence. This can be regarded as the private practice of forensic consultancy.

According to IEA 45, an opinion formed by an expert is based on recognized principles regulating the scientific study. The opinion so formed by a person having the necessary special skill in the subject is, therefore, the opinion of an expert in that branch of the science. Such an opinion is the opinion of an expert in a branch of science which is admissible in evidence under Section 45 of the Indian Evidence Act. (or)

One who has 10 years of experience dealing with similar types of cases as an expert – Similar kind of cases here means, there is plenty of complications involved in dealing with crime evidence. Hence, Experience will be vast and much expertise in nature. Many of the times experts may fail to form an opinion and where by the court will justify such conflict by itself being expert by considering other circumstantial evidence and facts of the case. Under section 73 IEA.

Though Section 73 deals with Comparison of signature, writing or seal with others admitted or proved. It has also relevance with the explanation given for court expertise.

Patna High Court State (Through Cbi) vs S.J. Choudhary on 13 February, 1996

Are there any designated experts recognized by the court?

Yes, Forensic Science Laboratories personnel’s under section 293 says Reports of certain Government scientific experts. Subsection 4 applies to the Government scientific experts, namely:-

(a) any Chemical Examiner or Assistant Chemical Examiner to Government; of Forensic Science Laboratories or Govt. Chemical Examiners Laboratory.

(b) the Chief Inspector of- Explosives; current position is Joint Chief Controller of Explosives (HOD) of Petroleum & Explosives Safety Organization (PESO).

(c) the Director of the Finger Print Bureau; both state level and central level.

(d) the Director, Haffkeine Institute, Bombay; as a bacteriology research Centre called the “Plague Research Laboratory”. It now offers various basic and applied biomedical science services.

(e) Director, Deputy Director or Assistant Director] of a Central Forensic Science Laboratory or a State Forensic Science Laboratory;

(f) the Serologist to the Government. Head of Institute of Serology that is Serologist & Chemical examiner or Assistant serologists.

So these people are regarded as experts in the court officially or they can also appoint assistants working with case actually under subsection 3 of Cr.P.C 293

 

This article will help to understand forensic expertise, the role of an expert in criminal justice system by providing suitable examples accordingly Indian Evidence Act Sections 45 & 73 and also gives a glance on government scientific experts under section 293 of Criminal Procedure Code.

via Forensic Expert — Forensic Science Public Desk, India

How to Catch a Liar via Brainwave Science

According to Brainwave Science an average person hears about 200 lies every day. It is no surprise as we learn how to lie in our early development stages and by the time we become adults, we get pro at lying! The only catch here is the question, ‘how to catch a liar?’

Technological advancements in different fields of crime scene investigation have drastically changed the landscape. Today, law enforcement can use technology to detect and solve criminal activity happening at the moment. The approach is more proactive than reactive. Forensic Science has completely changed the way crimes are investigated, prosecuted, and adjudicated.

Biometrics work very well to confirm the identity of the person. They are being utilized in ID cards, bank cards, phones, and other technological devices and come in various forms such as fingerprints, irises, voice patterns, and the spatial geometry of the faces, etc. Biometric systems must be able to accommodate changes to the biometric over time which may be caused by aging, illness, or injury.  Let us not forget though that external subject identification via its Automated Biometrics Identification System aims to ensure national security and public safety. It can only, however, identify the person’s identity externally, but not the mind and schemes of the person.

Brain Fingerprinting – This technique is quite ideal for discovering if a piece of information is collected in a person’s brain through EEG. It correctly measures the electric brainwaves science which helps us tap into the person’s familiarity with the crime scene. The major challenge in using this technique is the need for extensive training and the cumbersome nature of software and hardware application needs specialized neuroscientists to administer tests that may not be learned by investigators. It is more of a service-based model where the expert is needed to constantly conduct testing.

iCognative technology is the only available neuroscience-based forensic technology that is over 99.9% accurate, applicable in almost all investigations, is based on proven P300 science, has been used in over 100 real-life cases, and is virtually unbeatable. Today many countries and intelligence agencies in the world are already reaping the benefits afforded by it. To top it all it supports human rights and eliminates torture.

iCognative technology:

  • identifies criminals from innocents, detects presence or absence or information in the brain
  • specifically screens privileged information holders, specific training like IED/EOD bomb-making
  • helps apprehend terrorism and crime supporters and sympathizers
  • helps identify foot soldiers from kingpins in organized crimes
  • successfully detects intent to harm and cause violence

distinguishes between witness and perpetrator

DNA and Fingerprints are the first go-to methods for all investigations. They are accepted as a piece of evidence in the court of law. However, the issue with them is that the crime scene must remain uncorrupted and the collection of evidence must be done properly to eliminate cross-contamination. Preservation of these evidence is also a labor-intensive task that must be conducted by professionals who have been extensively trained in this field.

Lie Detector/Polygraphs are not accepted as evidence but are extensively used by law enforcement agencies to eliminate innocents from the suspects. The accuracy rates of Lie detectors or Polygraph has been hotly debated. People are able to beat them, and the interpretation of results is done subjectively by the examiner. Most psychologists agree that there is little evidence that polygraph tests can accurately detect lies – American psychological Association (APA)

 

Did you know that an average person hears about 200 lies every day? It is no surprise as we learn how to lie in our early development stages and by the time we become adults, we get pro at lying! The only catch here is the question, ‘how to catch a liar?’ Technol