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Forensics. Chapter 1: Introduction. Forensic Science: A Definition. Application of science to law Applies the knowledge and technology of science for the definition and enforcement of such laws.

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Chapter 1: Introduction

Forensic science a definition
Forensic Science: A Definition

  • Application of science to law

  • Applies the knowledge and technology of science for the definition and enforcement of such laws.

Forensic science is the application of science to those criminal and civil laws that are enforced by police agencies in a criminal justice system.

History and development
History and Development



Mathieu Orfila: Father of Forensic toxicology

Alphonse Bertillon: developed the science of anthropometry



Calvin Goddard: developed the comparison microscope for bullet comparisons.

Francis Galton: first study of fingerprints

More history
…more History



Principles of document examination

Microscopy as a tool for the forensic scientist



Developed the application of scientific principles to criminal investigations

Locard’s Exchange Principle

Locard s principle
Locard’s Principle

"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 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, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value.“

Organization of the crime lab
Organization of the Crime Lab

  • Over 320 public crime labs in the U.S…a tripling of the number since 1966.

  • Supreme Court decision Miranda v. Arizona (1966)

  • Increase in drug abuse

  • Advent of DNA profiling

  • Most State Governments maintain crime labs plus satellite labs.

Services of the crime lab

Physical Science Unit

Biology Unit

Firearms Unit

Document Examination Unit

Photography Unit

Toxicology Unit

Latent Fingerprint Unit

Polygraph Unit

Voiceprint Analysis unit

Evidence Collection Unit

Services of the Crime Lab

Physical science unit1
Physical Science Unit

  • Investigators:

    • Chemists

    • Physicists

    • Geologists

  • Items Identified:

    • drugs, glass, paint, explosives and soil

  • Job:

    • Analytical and chemical analysis

  • Biology unit1
    Biology Unit

    • Investigators:

      • Biologists

      • Biochemists

  • Identify and Compare:

    • botanical materials such as wood and plants.

  • Job:

    • Identification and DNA profiling of dried blood stains, other body fluids, comparison of hairs and fibers

  • Firearms unit1
    Firearms Unit

    • Identify and examine:

      • Firearms

      • Discharged bullets

      • Cartridge cases

      • Shotgun shells

  • Responsibility:

    • Examination of garments to detect firearm discharge residue

    • Determine approximate distance from target when weapon was fired.

  • Document analysis unit1
    Document Analysis Unit

    • Identify and Examine:

      • Handwriting and typewriting to determine authenticity and/or source

  • Job:

    • Analysis of paper and ink and indented writings (impressions)

  • Recreate:

    • Obliterations, erasures

    • Burned or charred documents

  • Photography unit1
    Photography Unit

    • Examine and Record:

      • Physical evidence at the scene

  • Specialize in:

    • Digital imaging, IR, UV, and X ray photography to make invisible information visible to the naked eye

  • Beyond the Scene:

    • Preparation of photographic exhibits for courtroom presentation.

  • Toxicology unit
    Toxicology Unit

    • Investigators:

      • Chemists

      • Biologists

  • Examine:

    • Body fluids and organs for the presence or absence of drugs and poisons.

    • Determines Blood alcohol content

  • Job:

    • Works with the coroner or medical examiner’s office

  • Latent fingerprint unit
    Latent Fingerprint Unit

    • Process and examine:

      • Fingerprints to determine possible matches with victims and suspects

    Polygraph unit1
    Polygraph Unit

    • Job:

      • Analyze respiration, perspiration, blood pressure and pulse rate to determine credibility

  • Used in conjunction with interrogation to determine credibility of suspects and witnesses.

  • Voiceprint unit1
    Voiceprint Unit

    • Interpret:

      • Telephone threats

  • Analyze:

    • Tape recorded messages

  • Compare:

    • Suspect voice recording to evidence to match source

  • Evidence collection unit1
    Evidence Collection Unit

    • CSI:

      • Crime Scene Investigation

  • Consists of:

    • trained personnel who are dispatched to the crime scene to collect and preserve physical evidence.

  • They simply collect the evidence, they do not do every single job as seen on fiction television.

  • Locard s principle revisited
    Locard’s Principle Revisited

    • Attempt the Hypothetical Case with a partner.

    • Answers:

      • Victim was inside the car means fibers from its interior have been transferred onto the victim’s clothing.

      • Blood from the victim has been transferred onto the velour interior.

      • Fiber, blood, hair, and skin cells may also have been transferred between the criminal and victim.

      • Tire tracks from the car may have been left in the woods.

      • This would probably lead to the make of car, since the tires are special.

      • If the vehicle was located, small driving imperfections in the tread could link it to the crime.

      • The type of soil at the crime scene may still be on the car’s tires, too.

      • Interior of suspect’s car could be tested for the fibers, hair, skin cells and blood of the victim.

    Types of law the three cs
    Types of Law – The Three Cs

    • Criminal

    • Civil

    • Common

      Note: there are others but these will be the primary ones in many of our cases

    • Probable Cause: situation in which a reasonable and prudent person, viewing the available informatio,n would conclude that a crime has been committed and that the suspect committed it

    Functions of the forensic scientist
    Functions of the Forensic Scientist

    • Frye v. United States: 1923 Rejection of Lie Detector (Polygraph) results necessitated guidelines for determining judicial admissibility of scientific examinations.

    • The Frye Standard: The court must decide if the questioned procedure, technique or principles are “generally accepted” by a meaningful segment of the scientific community.

    Daubert v merrel
    Daubert v. Merrel

    • Whether the scientific technique or theory can be tested.

    • Whether the technique or theory has been subject to peer review and publication.

    • The technique’s potential for error.

    • Existence and maintenance of standards controlling the technique’s operation.

    • Whether the scientific theory or method has attracted widespread acceptance within a relevant scientific community.


    Dr. Karow

    August 28, 1965

    Family physician, Karow, called to Coppolino home

    Carmela Coppolino

    Carmela’s remains


    Mary Gibson (Mary Coppolino – second wife)

    Circa 1966

    Marjorie Farber, widow of William Farber, mistress of Carl Coppolino


    Dr. Carl Coppolino

    Spring Chicken Gibson


    Mary Gibson (Mary Coppolino – second wife)

    July 30, 1963

    William Farber died

    Carl and his lawyer
    Carl and his lawyer

    Carl in custody

    Coppolino v state
    Coppolino v. State

    • M.E. testified that victim died of an overdose of a drug called succinylcholine chloride based on his toxicology report.

    • Succinylcholine chloride breaks down into succinic acid in the body.

    • This drug had never before been detected in a human body.

    • Defense argued that this test was new and absence of corroborative experimental data by other scientists.

    • The court rejected the defense’s argument on the grounds that although the tests may be new and unique, they are admissible only if they are based on scientifically valid principles and techniques.

    Expert testimony
    Expert Testimony

    • Must be competent: education degrees, member of applicable societies, published papers or books, etc.

    • Defense may cross-examine the

      potential expert witness.

    • The individual trial judge is the

      ultimate decision maker

      regarding expert witnesses.

    Training in recognition collection and preservation of evidence
    Training in Recognition, Collection, and Preservation of Evidence

    • Specially trained evidence collectors: CSI

    • On 24-hour call to aid criminal investigators in retrieving evidence

    • Specially equipped with all the proper evidence collection equipment

    • Unfortunately, some police forces still don’t use them or the police themselves have contaminated the crime scene before the CSI team gets there!

    Forensic pathology
    Forensic Pathology Evidence

    • Investigation of sudden, unnatural, unexplained, or violent death.

    • Medical Examiner vs Coroner = M.D. vs political appointee.

    • Autopsy:

    • Causes of death: natural, homicide, suicide, accident, undetermined.

    • Rigor mortis: starts within the first 24 hours and disappears after 36 hours. Helpful in estimating time of death. See “Algor mortis”

    • Livor mortis: settling of blood after the heart stops. Skin appears dark blue. Used to determine position of body at time of death.