The Evolution of Forensic Science in Criminal Investigations Part 1

Forensic science, the study of applying scientific principles and techniques to solve crimes, has helped develop invaluable methods used in modern criminal investigations. From the origins of early rudimentary practices such as collecting samples left by criminals and dusting for fingerprints, science has evolved into DNA analysis of minuscule material as well as sophisticated liquid chromatography to detect trace elements rarely found in nature. Even parental DNA has recently been used to find criminals.  With more and more advances, forensic science has made a huge impact on the modern criminal justice system led by a pursuit of the perfect test to solve crimes and avoid false convictions.

Forensic science can trace its roots back to the ancient practice of fingerprinting, where as early as  500 BC, Babylonians began incorporating fingerprints into clay tablets during business transactions. In later years, the Chinese used ink-on-paper finger impressions for both businesses identifying their children. These examples represent one of the earliest instances of using biological traits for identification. However, it wasn’t until the late 1700s that forensic science was being used as a factor to determine guilt or innocence in major criminal cases, including charges of murder. 

The 1784 case of John Toms marks one of the earliest known examples where forensic evidence was used to secure a conviction for murder. Edward Culshaw was found dead with a gunshot wound, and during the investigation, authorities discovered a torn piece of newspaper wadding inside the wound. The investigators noticed that the torn piece of newspaper seemed unusual, and they sought to find the source of this paper. When John Toms was apprehended as a suspect, a search of his belongings revealed a crumpled newspaper in his pocket. The key piece of evidence was that the torn piece of newspaper found in the wound perfectly matched the torn edge of the newspaper found in Tom’s possession. This connection between the torn newspaper in the victim’s wound and the matching piece in Tom’s pocket provided strong circumstantial evidence linking him to the crime. 

The success of the John Toms case shifted the focus of criminal investigations from relying solely on witness testimony and confessions to incorporating physical evidence as a reliable means of establishing a verdict. For example, the introduction of fingerprinting as a unique identifier, the study of ballistics, and the use of toxicology all stem from the early recognition that physical evidence could be key in solving crimes. As forensic science continued to evolve, these early innovations paved the way for more systematic and scientifically grounded approaches to criminal investigations. By the early 1900s, fingerprinting had become a crucial tool in criminal investigations, providing a unique and reliable method for identifying individuals. The first known conviction based on fingerprint evidence occurred in 1902 when Harry Jackson was convicted of burglary in London after his fingerprints were found on a windowsill. By the 1920s, fingerprinting had become a standard practice in police work worldwide.