Criminalistics week 1 (full)

Week 1: Lesson 1 Overview

• Introduction and assessing crime scene evidence.

• Importance of forensic science in enhancing safety and wellbeing in everyday life.

Forensic Science Contributions to Society

• Determines if a crime was committed.

• Establishes how and when a crime occurred.

• Identifies victims and the sequence of events.

• Enhances safety in various sectors:

  • Automobile safety

  • Fire prevention and suppression

  • Food and drug safety

  • Public place safety (e.g., amusement parks)

  • Transportation safety

• Forensic science connects science to civil and criminal law, highlighting its importance in monitoring behavior impacting society.

• Media portrayal often influences public perception, focusing primarily on criminal justice applications.

Understanding Scientific Method and Criminalistics

• Importance of understanding complexities when reconciling forensic science with the law.

• Contrasting methods of decision-making in science versus legal systems.

History and Development of Forensic Sciences

• Emergence of methods to classify and compare physical evidence integrated with legal needs.

Media Representation of Forensic Science

• Positive Aspects:

  • Increased public awareness.

  • Better-informed citizens.

  • Heightened scrutiny of law enforcement.

• Negative Aspects:

  • Misperceptions about crime types and the justice system.

  • Increased fear of crime.

  • Added pressure on law enforcement agencies.

• Recognizing that a small percentage of evidence is collected; resource limitations may lead to crime prioritization based on significance and profile.

• Evidence mishandling occurs more frequently than recognized, particularly in specific regions.

Influential Figures in Forensic Science

• Sir Arthur Conan Doyle:

  • Influenced public perception through "Sherlock Holmes" series, early promotion of scientific methods in crime-solving.

• Mathieu Orfila:

  • Founder of forensic toxicology; wrote about poisons and their effects, linking forensic findings to the legal framework.

  • Emphasized the relationship between arsenic in soil and poisoning.

• Alphonse Bertillon:

  • Developed anthropometry for personal identification; introduced systematic body measurements leading to criminal identification.

• Francis Galton:

  • Conducted first fingerprint analysis; established classification methodologies for fingerprinting.

• Leone Lattes:

  • Innovated methods to identify blood types from dried stains, enhancing identification techniques in serology.

• Calvin Goddard and Albert Osborn:

  • Focused on ballistic analysis and document examination, respectively, improving investigative techniques.

• Walter C. McCrone:

  • Renowned for advancements in microscopy and trace analysis.

• Edmond Locard:

  • Established Locard's Principle of Exchange, highlighting evidence transfer between crime and criminal.

Crime Laboratory Services

• Purpose: Research facilities applying forensic technology to analyze evidence from criminal cases.

• Basic Units:

  • Physical Science Unit (chemical testing).

  • Biology Unit (DNA profiling).

  • Firearms Unit (ammo examination).

  • Document Examination Unit (authenticity analysis).

  • Photography Unit (forensic evidence documentation).

• Optional Units:

  • Toxicology Unit (substance analysis of fluids and tissues).

  • Latent Fingerprint Unit (processing fingerprint evidence).

Role of Forensic Scientists

• Critical in gathering, analyzing, and interpreting physical evidence.

• Main tasks include:

  • Evidence analysis and expert testimony.

  • Training on evidence recognition, collection, and preservation.

Evidence Collection and Analysis

• Focus on physical evidence, which serves as a link between crime, victim, and perpetrator.

• Different types of evidence include biological samples, documents, drugs, firearms, and more.

• Identification Process: Determines physical or chemical identity with high certainty.

• Individualization: Assesses whether particular evidence can be traced back to a specific origin.

Testimonial Evidence

• Relies on witness accounts or previous knowledge.

• Types include personal and physical descriptions, influenced by various factors.

• Reliability is key, with numerous factors affecting it, including perceptivity, emotional state, and prejudices.

• Techniques to enhance the accuracy and objectivity of testimonies:

  • Comparisons and sketches.

  • Voice and ear identification.

  • Identification parades for suspect recognition.

Modus Operandi (MO)

• Defines a criminal's method of operation.

• Influenced by various factors such as psychological variables, prior experiences, and opportunity.

• Essential for identifying patterns in criminal behavior and linking crimes.

• Phases of MO: Planning phase (premeditation) and operational phase (execution).