The application of scientific methods to examine the evidence gathered in order to solve queries, thereby helping the legal system to acknowledge the truth is known as forensic science. The evidence may range from fingerprints to blood samples, or from a memory card to a hard disk. The word 'forensic' was derived from the Latin word 'forensis', meaning 'before the forum'.
Forensic Science History
The first documented use of medical knowledge to solve a crime can be traced to a Chinese book titled Xi Yuan Ji Lu or 'Collected Cases of Injustice Rectified', written by Song Ci in 1248. It contained description of how to distinguish death due to drowning from death due to strangulation.
The 18th and 19th centuries saw a great deal of progress in the field of forensic science in Europe. One of the first recorded instances of its application in solving a legal case came in 1784, in England, when a torn piece of paper recovered from the bullet wound in the victim's head matched the other piece of paper from John Tom's pocket and led to his conviction.
Fortunatus Fidelis, an Italian doctor, is regarded as the first person to practice modern forensic medicine, way back in 1598. Later, in the 19th century, forensic medicine became a recognized branch of medicine. In 1806, German chemist, Valentin Ross developed a method to detect poison in the walls of the victim's stomach. In a murder trial in 1836, James Marsh was able to identify arsenic intake as the cause of death with the help of forensic science.
Edmond Locard, a renowned criminologist from France, formulated the basic principle of forensic science, which says, "Every contact leaves a trace". In 1910, he established the world's first laboratory dedicated to crime analysis in association with the Lyons Police Department. His seven volume work, Traité de Criminalistique proved to be of great help in many investigations. In 1932, the Federal Bureau of Investigation (FBI) established its own forensics laboratory―the Federal Crime Laboratory, with J. Edgar Hoover as its director.
Over the period, forensic science has been broadly divided into a few subdivisions. While digital forensics is applied to prove scientific methods and techniques to recover data from digital media, forensic toxicology is applied to determine the effects of drugs and poison on living beings. Similarly, forensic anthropology is utilized to recover and identify skeletal remains and veterinary forensics to solve crimes involving animals.
Forensic DNA Analysis
The DNA of every person is unique, with the only exception being identical twins. An individual's DNA profile can be generated by using samples of blood, bone, or hair. Analyzing the DNA samples collected from the crime scene with those of the suspect for the presence of a set of specific DNA markers can serve as the proof of crime. DNA profiling was first described by an English geneticist, Alec Jeffreys in 1985. It was first used in England to convict Colin Pitchfork for the murder of two girls. In the United States, the first instance came with the conviction of Tommy Lee Andrews for the case related to a series of sexual assaults.
The last two decades have seen a tremendous rise in the use of DNA evidence to solve criminal cases and also for paternity detection. Today, forensic science is used in the investigation of every major crime, with a few hundred forensic laboratories contributing to the cause in the United States alone. Its popularity in the law enforcement community plays a crucial role in ensuring that justice prevails.