Basics of Forensic Science
Synopsis
- Introduction
- Areas of Forensic Science
- Modern Forensic Science
- Crime Novels
- First Forensic Laboratory
- Forensic Science Sections
- Fingerprint Impression
- Bloodstain Pattern Analysis
- Conclusion
- Reference
Introduction
Forensics involves observations and experiments conducted using scientific techniques. It is defined as the inspection of the reliability and validity of the evidence, leading to a logical conclusion based on the evidence.
1.Forensic Medicine - Doctors investigating a body to determine the cause of injuries or death.
2.Forensic Science - Specialists investigating drugs, ballistics, DNA, documents, physical evidence, and fingerprints.
Areas of Forensic Science
# Archaeology = Reconstructing the past events.
# Arts = Examining the originality of artifacts.
# Disasters = Reconstructing disaster events.
# Politics = Prosecution of war criminals.
# Crime = Identification of suspects.
# Sports = Testing for drugs.
Modern Forensic Science
The French Criminologist Edmond Locard (1877 - 1966) is considered the father of modern forensic science.
One of his famous quotes was "every contact leaves a trace", which came to be known as Locard's exchange principle. He went on to say that "wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints but also his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects – all of these and more bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong; it cannot perjure itself, and it cannot be wholly absent. Only human failure to find it, study, and understand it can diminish its value".
Crime Novels
Sir Arthur Conan Doyle (1859 - 1930) was a Scottish doctor who, having an unsuccessful career, turned to writing stories to fill his free time. He played a major role in conceptualising forensics through literature with his Sherlock Holmes book series, long before forensics gained recognition as an investigative tool in legal proceedings.
First Forensic Laboratory
# In France, the first forensic laboratory was founded by Edmond Locard in 1910.
# In Canada, the first forensic laboratory was founded by Lomer Gouin in 1914.
# In Germany, the first forensic laboratory was founded by Robert Heindl in 1915.
# In the United States, the first forensic laboratory was founded by Los Angeles Police Department (L.A.P.D) Chief August Vollmer in 1924 and the Federal Bureau of Investigation (FBI) crime laboratory was founded in 1932.
# In the United Kingdom, the first forensic laboratory was founded by Metropolitan Police Service (M.P.S - Scotland Yard) in 1935.
# In India, the first forensic laboratory was founded by Dr. B.C. Roy in 1952 in Kolkata.
Forensic Science Sections
# Physical Science = Analysis of physical and chemical properties to compare and identify evidence through chemical tests, microscopy, spectroscopy, fragments, and explosives.
# Voice Analysis = Identification of speech, language, speaker, gender, emotion, age, and locating keywords from the speech.
# Criminal Profiling = Analysis of behavioral characteristics to assess whether he/she is likely to have committed a crime.
# Documents = Analysis of faked and forged documents through handwriting, prints, paper, and ink scrutiny.
# Hair Analysis = Extraction of DNA from hair samples to identify the suspect and victim.
# Polygraph = Detection of changes in physiological characteristics using a lie detector.
# DNA Profiling = Analysis of DNA is crucial and the most reliable evidence in forensics.
# Cyber Forensic = Focusing on the recovery of digital data and electronic trails.
# Firearms = Analysis of guns, bullets, cartridge cases, and firearm damages.
# Photography = Identification of real and fake photographs.
# Forensic Odontology = Evaluation of dental evidence.
# Forensic Toxicology = Examination of drugs and poisons.
# Forensic Entomology = Analysis of insects related to the crime.
# Forensic Geology = Analysis of various minerals found on the earth to know the composition rates.
# Forensic Anthropology = Analysis of the skeleton is a helpful technique used when the body is found after decomposition.
# Forensic Facial Reconstruction = Reconstruction of the skull using the clay method or graphical method to identify the person.
# Forensic Serology = Detection of biological materials like blood, semen, saliva, and urine to link the suspect and victim to the scene.
# Forensic Botany = Study of botanical evidence like pollen, spores, seeds, leaves, flowers, fruits, and wood in establishing relationships among articles, place, suspect, and victim.
Fingerprint Impression
Fingerprint impressions are used for the identification of individuals since they don't change over a person's lifetime, and no two fingerprints are exactly the same, even among identical twins. Consequently, fingerprints are widely employed in criminal cases to identify both suspects and victims.
The ancient usage of fingerprints can be traced back to the Babylonian empire and the Chinese Qin empire, while the modern application of fingerprints can be traced to the British Raj. In July 1858, Jangipur Chief Magistrate William James Herschel collected fingerprints from the local businessman Rajyadhar Konai to seal official documents for a government deal.
In the 1880s, Mark Twain and Francis Galton (cousin of Charles Darwin) gained fame for popularising the usage of fingerprint analysis. Mark Twain incorporated fingerprints into his fiction books, 'Life on the Mississippi' (1883) and 'Pudd'n Head Wilson' (1894), using them to identify a murderer.
Anthropologist Francis Galton studied fingerprints for individual identification and established the systematic classification of fingerprints. He published 'Finger Prints' (1892), 'Decipherment of Blurred Finger Prints' (1893), and 'Fingerprint Directories' (1895). Argentine Police Officer Juan Vucetich began the first fingerprint files based on Francis Galton's fingerprint pattern analysis.
Bloodstain Pattern Analysis
Bloodstain Pattern Analysis (BPA) is an important tool in the forensic serology section, used to reconstruct the crime scene by analyzing the amount of blood and the types of patterns.
Impact spatter occurs when a weapon strikes a victim, resulting in circular bloodshed rather than elongated patterns. Back spatter happens when blood splatters on the attacker, while forward spatter occurs when blood leaks from the victim's wound and splatters on nearby surfaces. The speed of the weapon used in the attack can affect the magnitude of the blood spatter, and the attack can be classified as high, medium, or low velocity.
# Gunshot wounds yield little droplets due to High-Velocity Splatter, which typically occurs at a speed of 100 feet per second and produces blood droplets that are 1 millimeter in diameter or smaller.
# Medium-Velocity Splatter refers to bodily harm induced by a strong blow with a dull object, resulting in cast-off blood patterns. In this category, blood droplets ranging from 1 to 4 millimeters in length are typically created at velocities of 5 to 25 feet per second.
# Blood dripping from a person usually causes Low-Velocity Spatter.
Conclusion
Forensic Science is an important tool for investigating and researching civil or criminal cases. It is used to determine the nature, cause, time, and answer relevant 'WH' questions concerning murders, accidents, crashes, theft, and frauds. The agenda of forensic scientists is to establish whether the cause was accidental, environmental, occupational, deliberate murder, or foul play (duplicity).
Reference
Galton Fingerprints
Science of Forensic
Overview of Digital Forensic
Introduction to Forensic Science (NTU)
Father of Forensic Science Branches
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