FRSC 1011: Introduction to Crime Scene Investigation

Introduction to Forensic Science

Definition: Forensic science applies scientific principles to criminal and civil law. It integrates various scientific disciplines to examine evidence within the framework of the justice system. Forensic science plays a crucial role in solving crimes, providing reliable evidence that can be used in court to support prosecutions and defenses alike.
Requirements for Forensic Investigation:

• Development of principles and techniques for identifying and comparing physical evidence.
• Application of these principles in a practical manner within the criminal justice system, which includes ensuring that methods are validated and that results are reproducible.
• Collaboration among forensic scientists, law enforcement, and legal professionals to ensure that all evidence meets legal standards for admissibility.

Historical Development of Forensic Science

Historical Overview: Forensic science has evolved over centuries, with various key individuals contributing to its development. The principles and practices have advanced significantly from rudimentary techniques to highly sophisticated methodologies used today.
Early Works:

• 3rd Century China: The Yi Yu Ji documented criminal cases, significantly a case involving the burning of a husband and the use of animal experiments for evidence. This case is one of the earliest documented instances of forensic analysis and demonstrates an early understanding of the importance of evidence in legal investigations.

Key Individuals in Forensic Science

Fingerprinting:

• Marcello Malpighi (1686): First recorded observations on fingerprint characteristics, noting that fingerprints are unique to each individual.
• Late 1800s: Thomas Taylor and Henry Faulds proposed the use of fingerprints for identification, suggesting that they could be a reliable means for establishing someone's identity, which laid the foundation for modern fingerprinting practices.
• Francis Henry Galton (1892): Pioneered fingerprint classification and established the uniqueness of fingerprints, significantly contributing to criminal identification procedures.
  Alphonse Bertillon (1879): Developed anthropometry, the first systematic method of identifying individuals based on body measurements, which served as the precursor to modern biometrics. His method was widely used until it was superseded by fingerprinting.
  Hans Gross (1893): Author of "Criminal Investigation," explored the application of multiple scientific disciplines in forensic investigations, establishing forensic science as a distinct field and emphasizing the need for scientific rigor in investigations.

Advances in Chemistry and Toxicology

Pioneering Chemists:

• Carl Wilhelm Scheele (1775): First to detect arsenic in remains, marking a significant advancement in toxicology.
• Mathieu Orfila (1814): Published treatises on toxicology that laid the groundwork for forensic toxicology, emphasizing its role in determining the cause of death and the investigation of poisonings.
  20th Century Innovations:
• Dr. Karl Landsteiner (1901): Discovered blood grouping, crucial in forensic DNA analysis, enabling scientists to match blood samples from crime scenes to potential suspects.
• Dr. Leon Lattes: Developed methods for blood type determination from dried stains, advancing the ability to analyze and utilize blood evidence collected in various conditions.
• Edmond Locard: Formulated the Exchange Principle, stating that every contact leaves a trace, which is foundational for tracing criminal activity and gathering evidence.

Modern Scientific Methods in Forensics

Technological Advances:

• Utilization of sophisticated techniques such as chromatography, spectrophotometry, and DNA typing, which have revolutionized the field by increasing the accuracy and reliability of forensic analysis.
• Sir Alec Jeffreys (1984): Developed the first DNA profiling test, leading to the identification of criminals through biological evidence and transforming criminal investigations.
  Case Study - The Pitchfork Murder Case:
• Utilized DNA evidence to exonerate an innocent suspect and convict the actual perpetrator, highlighting the reliability of DNA profiling and its role in justice. This case exemplifies the power of forensic science to correct miscarriages of justice.

Crime Laboratories and Evidence Analysis

Crime Lab Functionality:

• Basic units include: physical sciences, biology, firearms, documentation examination, and photography. Each unit specializes in a specific aspect of forensic investigation, allowing for comprehensive analyses of evidence.
• Optional services may support forensic pathology, anthropology, and other specialized analysis, ensuring cases can be handled holistically.
  Key Legal Cases:
• Frye v. United States: Set the precedent that scientific evidence must be generally accepted in the scientific community, establishing criteria for the admissibility of scientific evidence in court.
• Daubert v. Merrell Dow Pharmaceuticals: Expanded criteria for admissibility of scientific evidence to include relevance and reliability, impacting how scientific evidence is assessed in legal proceedings.

Importance of Note Taking in Crime Scene Investigation

Effective Note Taking:

• Critical for capturing the time, place, and conditions of a crime scene. Accurate documentation is essential for reconstructing events and supporting the investigation.
• Ensures accuracy and reliability of recorded observations, providing essential context for investigations. Notes must detail all observations, including the condition of the scene and the location of evidence.
• Must be clear, detailed, and legibly written at the moment of investigation to prevent reliance on memory, which can be fallible.
  Documentation and Chain of Custody:
• Chain of custody is crucial for maintaining the integrity of evidence from collection through to courtroom presentation, ensuring that evidence has not been tampered with and can be trusted in a legal context.