Chapter 1 - Introduction

1
Chapter 1 - Introduction

• Basics of Forensic Science

2
Definition and Scope

• Forensic science is the application of science to
  law
• Applies the knowledge and technology of science
  to the definition and enforcement of laws
• Laws are continually being broadened and revised
  to address the alarming increase in crime rates

3
The Role of Science

• Science cannot offer final and authoritative
  solutions to all problems
• Social and psychological factors are always
  present
• Science plays an important and unique role in the
  criminal justice system ability to supply
  accurate and objective information that reflects
  events that have occurred at a crime scene

4
Definition of Forensics Science

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

5
Diversity of Professions Involved

• According to the American Academy of Forensic
  Science
• Criminalistics (synonym for forensic science)
• Engineering Science
• General
• Jurisprudence
• Odontology
• Pathology/Biology
• Physical Anthropology
• Psychiatry/Behavioral Science
• Questioned Documents
• Toxicology

6
Additions to the list of 10

• Fingerprint examination
• Firearm and tool mark examination
• Technology analysis
• Computers
• Digital data analysis
• Photography

7
History and Development

• Individuals who developed the principles and
  techniques needed to identify or compare physical
  evidence
• Those who recognized the need to merge these
  principles into a coherent discipline that could
  be practically applied to a criminal justice
  system

8
Early Developments

• One of the earliest records
• 3rd century China manuscript Yi Yu Ji
• Case solved where a woman was suspected of
  murdering her husband
• Evidence showed that he was murdered and she
  admitted her guilt
• Chinese were also the first to recognize the
  potential of fingerprints for identification
  purposes
• Often the exception rather than the rule for
  criminal investigations

9
Early Developments (continued)

• Limited knowledge of anatomy and pathology
• Hampered the development of Forensic Science
  until late 17th and early 18th centuries
• First recorded notes about fingerprint
  characteristics
• 1686, Marcello Malpighi
• Did not acknowledge the value of fingerprints as
  a method of ID

10
Initial Scientific Advances

• 1798 A Treatise on Forensic medicine and Public
  Health
• François-Emanuel Fodéré
• Breakthroughs in chemistry also helped
• 1775 Carl Wilhelm Scheele devised first
  successful test for detecting arsenic in dead
  bodies

11
Initial Advances (continued)

• 1814 Mathieu Orfila
• Father of forensic toxicology
• Published the first scientific treatise (study)
  on the detection of poisons and their effects on
  animals
• Mid-1800s
• Advance of several scientific disciplines which
  advanced the field of forensics
• 1828 William Nichol polarizing microscope
• 1839 Henri-Louis Bayard microscopic detection
  of sperm
• 1839 toxicological evidence first used at a
  trial
• 1853 microcrystalline test for hemoglobin
• 1863 first presumptive test for blood
• 1850s and 1860s use of photography in forensics

12
Late 19th-Century Progress

• Beginning to apply knowledge from all scientific
  disciplines to the study of crime
• Anthropology/Morphology (structures of living
  organisms) applied to the first system of
  personal identification
• 1879 Alphonse Bertillon
• Named anthropometry systematic procedure for
  using a series of body measurements as a means of
  distinguishing one person from another (later
  replaced by fingerprinting)
• Father of Criminal Investigation

13
More on the 19th century

• Bertillons anthropometry later replaced by
  fingerprinting
• Thomas Taylor (American) said that fingerprints
  could be used for ID
• Supported by Scottish physician Henry Faulds
• 1892 Francis Henry Gaulton undertook the first
  definitive study of fingerprints and developed a
  method for classifying them

14
Sherlock Holmes

• Not a real person
• Legendary but fictional detective in stories by
  Sir Arthur Conan Doyle
• Had a considerable influence on popularizing
  crime-detection methods
• Applied newly developing principles of serology
  (blood/body fluids), fingerprinting, firearms ID
  and document analysis in his stories
• Doyles A Study in Scarlet is a classic example
  (see excerpt)

15
20th Century Breakthroughs

• 1901 Karl Landsteiner
• Discovered ABO blood types
• 1910 Albert S. Osborne
• Wrote the first significant text on Questioned
  Documents (document examination)
• 1915 Dr. Leon Lattes
• Developed a simple procedure for identifying the
  blood group from a dried blood stain
• Immediately applied to criminal investigations
• Acceptance of documents as scientific evidence by
  the courts
• 1923 Calvin Godddard
• Used comparison microscope to refine techniques
  of firearms examination

16
Edmond Locard

• French
• Formal education in both medicine and law
• Started the first police lab in 1910
• Founder and director of the Institute of
  Criminalistics _at_ the University of Lyons (France)
• Leading international center for study and
  research in forensic science
• Strongly believed every criminal can be connected
  to a crime by dust particles carried from the
  crime scene
• Locards successes helped start police labs in
  Vienna, Berlin, Sweden, Finland and Holland

17
Locards Exchange Principle

• When two objects (or people) come in contact with
  each other, a cross-transfer of materials occurs

18
Modern Scientific Advances

• Mid-20th century
• Revolution in computer technology
• Dramatically impacted the field of forensics
• Wide array of sophisticated techniques for
  analyzing evidence available
• Chromatography
• Spectrophotometry (measuring the
  absorption/reflection of light by materials)
• Electrophoresis

19
DNA

• Most significant modern advance
• DNA typing and profiling
• 1984 Sir Alec Jeffries developed the first DNA
  profiling test
• 1986 DNA profiling used to solve the Pitchfork
  murders of two young English girls (Colin
  Pitchfork)
• Precise ID of a suspect can be determined

20
Computer Databases

• Fingerprints
• Bullets and shell casings
• DNA
• Significantly reduced the time it takes to
  analyze evidence and increase accuracy of the
  results

21
Key Points

• Forensic science is the application of science to
  criminal and civil laws that are enforced by
  police agencies in a criminal justice system
• The first system of criminal ID was called
  anthropometry. It distinguished one individual
  from another based on a series of body
  measurements
• Forensic science owes its origins to individuals
  such as Bertillon, Gaulton, Lattes, Goddard,
  Osborne and Locard, who developed the techniques
  needed to identify or compare physical evidence.
• Locards Exchange Principle states that when two
  objects come in contact with each other, a
  cross-transfer of materials occurs that can
  connect a criminal suspect to his/her victim.

22
Crime Laboratories - History

• 1923 Los Angeles Police Dept. crime lab is the
  oldest
• Established by August Vollmer
• 1948 School of Criminology formed at UC-Berkley
• 1932 FBI established under President Herbert
  Hoover
• Offered forensic services to all law enforcement
  agencies in the USA
• 1981 Forensic Science research and Training
  Center for research and development of new
  techniques/tools/methods
• Train lab personnel in the latest techniques
• Most labs are run locally or at the state level

23
Organization of a Crime Lab

• Characterized by rapid growth
• Lack of national/regional planning/coordination
• Levels federal, state, county, municipal
• Size and diversity makes it impossible to adopt a
  single model of operation
• Most function as part of the local police
  department, prosecutor, district attorney or
  medical examiner (coroner)

24
Growth

• Several reasons explain the rapid growth of crime
  labs in the past 40 years
• Supreme Court decisions requiring scientific,
  objective treatment of evidence
• Constitutional rights of suspects (Miranda
  Rights)
• Changing judicial requirements due to the
  staggering increase in crime rates in the USA,
  especially drug-related crime
• DNA technology/profiling needs more qualified
  personnel to analyze the evidence
• Drug cases still outnumber DNA cases

25
Crime Labs in the USA

• Desire to retain local control
• Produced a variety of independent labs
• Government has no single law enforcement agency
  with unlimited jurisdiction

26
Crime Labs in the USA (continued)

• FBI (Department of Justice)
• Maintains the largest crime lab in the world
• Ultramodern facility located in Quantico, VA
• DEA (Drug Enforcement Administration -
  (Department of Justice)
• Analyzes drugs seized in violation of federal
  laws regulating production, sale and transport
• ATF (Alcohol, Tobacco and Firearms)
• Analyzes alcoholic beverages
• Examines documents related to alcohol and firearm
  excise tax law enforcement
• Examines weapons, explosive devices and related
  evidence
• Gun control Act of 1968
• Organized crime Control Act of 1970
• U.S. Postal Service
• Criminal investigations related to the postal
  service

27
Local and International Crime Labs

• Most state governments maintain a crime lab some
  wit regional or satellite offices (larger states)
• Try to be cost-effective by not duplicating
  services
• Most countries have created and maintain
  facilities
• Organization can vary from country to country
• Often operate on a fee-for-service basis (some
  can be private companies)

28
Services of the Crime Lab

• Wide variation in total services offered
• There are many reasons for this
• Variations in local laws
• Different capabilities/functions of the
  organization to which the lab is attached
• Budgetary and staffing limitations (often very
  limited)
• Some labs have strict functions like processing
  drug specimens only

29
Basic Services

• Physical Science Unit
• Principles of chemistry, physics and geology
• ID/comparison of crime-scene evidence
• Biology Unit
• Biologists/biochemists
• DNA profiling, ID/comparison of biological
  evidence including botanical materials
• Firearms Unit
• Examines firearms, discharged bullets, cartridge
  cases, shotgun shells, ammunition, residues, tool
  marks
• Determine composition, distance, angles
• Document Examination Unit
• Handwriting/typewriting on questioned documents
• Ascertain authenticity/source
• Photography Unit
• Examines/records photographic evidence
• Uses highly specialized techniques such as
  digital imaging, IR, UV, X-ray to make invisible
  images/information visible

30
Optional Services Provided by a Full-service
Crime Lab

• Toxicology Unit
• Examines body fluids/organs to determine the
  presence/absence of drugs
• Latent Fingerprint Unit
• Processes and examines fingerprint evidence
• Polygraph Unit
• Lie detecting
• Voiceprint Analysis Unit
• Involves cases of telephone threats or recorded
  messages
• Trained analysts tie the voice to a suspect
• Sound spectrograph creates a voiceprint
• Sound patterns produced in speech are unique

31
Optional Services (continued)

• Crime-Scene Investigation Unit
• Dispatched specially trained personnel to a crime
  scene to collect/preserve evidence to be analyzed
  later in the lab
• Includes forensic pathology, entomology and
  anthropology
• Forensic Psychiatry
• Examines the relationship between human behavior
  and legal proceedings
• Behavior patterns of criminals/behavior profile
• Forensic Odontology
• ID victims based on dental evidence
• Bite mark analysis linked to tooth structure on a
  suspect
• Forensic Engineering
• Failure analysis, accident reconstruction,
  causes/origins of fires/explosions
• Forensic Computer/Digital Analysis
• Identifying, collecting, preserving and examining
  information derived from computers/digital devices

32
Key Points

• The development of crime labs in the USA has been
  characterized by rapid growth accompanied by a
  lack of national and regional planning and
  coordination
• Four major reasons for the increase in the number
  of crime labs in the USA since the 1960s are as
  follows
• The fact that the requirement to advise criminal
  suspects of their constitutional rights, right to
  immediate access to counsel has all but
  eliminated confessions as a routine investigative
  tool
• The staggering increase in crime rates in the USA
• The fact that all illicit drug seizures must be
  sent to a lab for confirmatory chemical analysis
  before a case can go to court
• The advent of DNA profiling
• The technical support provided by crime labs can
  be assigned to 5 basic services
• Some crime labs offer optional services such as
  toxicology, fingerprint analysis, polygraph
  administration, voiceprint analysis, and
  crime-scene investigation.
• Special forensic services available to the law
  enforcement community include forensic pathology,
  entomology, psychiatry, odontology, engineering,
  computer/digital analysis.

33
Functions of the Forensic Scientist

• Analyzing Physical Evidence
• Apply principles of physical/natural sciences in
  analyzing evidence
• Only physical evidence is free of error/bias
• Must undergo scientific inquiry the integrity
  of evidence comes from applying the scientific
  method
• Not tainted by human error/distortion of facts

34
Functions of the Forensic Scientist (continued)

• Determining the admissibility of evidence
• Frye vs. The United States
• Procedures/techniques/principles are generally
  accepted by the scientific community
• Federal Rules of Evidence
• Governs admissibility of evidence including
  expert testimony on a scientific/technical matter
  if
• Testimony is based on sufficient facts/data
• Testimony is the product of reliable
  principles/methods
• Witness has applied the principles/methods
  reliably to the facts of the case
• (also used in state courts)

35
Functions of the Forensic Scientist (continued)

• Judging Scientific Evidence
• Judge assumes ultimate responsibility for
  admissibility/reliability of evidence
• The Court offers some guidelines
• Whether the scientific technique/theory can be
  tested
• Whether the scientific technique/theory has been
  subject of peer review/publication
• Techniques potential rate of error
• Existence/maintenance of standards controlling
  the techniques operation
• Whether the scientific technique/method has
  attracted widespread acceptance within the
  relevant scientific community
• Providing Expert Testimony
• Performing the analysis of evidence
• May be required to testify in court about their
  methods, etc.
• Education/training is very important

36
Key Points

• A forensic scientist must be skilled in applying
  the principles and techniques of the
  physical/natural sciences to analyzing evidence
  that may be recovered during a criminal
  investigation.
• The cases Frye vs. the United States and Daubert
  vs. Merrell Dow Pharmaceuticals, Inc. set
  guidelines for determining the admissibility of
  scientific evidence into the courtroom.
• An expert witness evaluates evidence based on
  specialized training/experience.
• Forensic scientists participate in training law
  enforcement personnel in the proper recognition,
  collection and preservation of physical evidence.