forensic science chapter 1 notes

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< FORENSIC SCIENCE CHAPTER 1 NOTES
Outcomes: After studying this chapter you should be able to:
* Define and distinguish forensic science and criminalistics
* Recognize the major contributors to the development of forensic science
* Account for the rapid growth of forensic laboratories in the past forty years
* Describe the services of a typical comprehensive crime laboratory in the criminal justice
system
* Compare and contrast the Frye and Daubert decisions relating to the admissibility of
scientific evidence in the courtroom
* Explain the role and responsibilities of the expert witness
* Understand what specialized forensic services, aside from the crime laboratory, are generally available to law
enforcement personnel
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1-1 Definition and Scope of Forensic Science
< The word forensics means to verbally debate in public.
< Forensic science is the application of science to matters of law. It applies the knowledge and technology of science
for the definition and enforcement of such laws.
< Each year science merges more closely with civil and criminal law as government deems it necessary to regulate
activities which influence our daily lives. The Food & Drug Administration and Environmental Protection
Agencies are examples of this.
< Criminal justice laws are continually being revised in response to increasing crime rates.
< Science does not offer absolute authoritative solutions, however it does supply accurate and objective information
about what occurred at a crime scene.
< Forensic science is a very broad and comprehensive field of study. It is the application of science to those criminal
and civil laws that are enforced by police agencies in a criminal justice system.
< Forensic science and criminalistics are interchangeable terms. Criminalistics is a narrower term, indicating the
services of a crime laboratory.
1-2 History & Development of Forensic Science
< The first “CSI” was Sir Arthur Conan Doyle’s (1859 - 1930) Sherlock Holmes series. This character popularized
scientific crime-detection methods. Holmes applied blood-typing, fingerprinting, and other testing before they were
popular for real-life criminal investigations.
< Forensic science owes its origins to individuals such as Bertillon, Galton, Lattes, Goddard, Osborn, and Locard,
who developed the principles and techniques needed to identify or compare physical evidence.
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Who They Are
Where
They
Lived
Lived from/to
What They Did
When
They
Did It
Mathieu Orfila
Spain
1787 - 1853
“Father of Forensic Toxicology” - published the first
scientific paper on detecting poison in animals.
1814
Alphonse Bertillion
France
1853 - 1914
Devised the first scientific system of personal
identification. Anthropometry is a systematic
procedure of taking a series of body measurements
as a means of distinguishing individuals.
1879
Francis Galton
England
1822 - 1911
Conducted the first definitive study of fingerprints
and their classification. Published Finger Prints.
1892
Hans Gross
Austria
1847 - 1915
Wrote the first paper describing the application of
scientific principles to the field of criminal
investigation. Published Criminal Investigation.
1893
Edmond Locard
France
1877 - 1966
Incorporated Gross’ principles within a workable
crime laboratory; became the founder and director
of the Institute of Criminalistics at the University of
Lyons.
1910
Albert S. Osborn
U. S.
1858 - 1946
Developed the fundamental principles of document
examination; published Questioned Documents.
1910
Leone Lattes
Italy
1887 - 1954
Developed a procedure to determine blood type
(serology) from dried bloodstains. (Karl Landsteiner
discovered blood groups in 1901.)
1915
Calvin Goddard
U. S.
1891 - 1955
Used a comparison microscope to determine if a
particular gun fired a bullet.
1925
Walter C. McCrone
U. S.
1916 - 2002
A preeminent microscopist who utilized microscopy
and other analytical methodologies to examine
evidence.
1970
< Locard believed that a cross-transfer of evidence occurred every time a
criminal came in contact with an object or person. This is called Locard’s
Exchange Principle.
< Locard’s successes served as the impetus for the formation of police
laboratories in several countries during the post-World War I period.
< The oldest US forensic lab was created in 1923 in Los Angeles by August
Vollmer, a police chief from Berkeley, California. California has an
integrated forensic system, linking regional laboratories with satellite
facilities.
< National forensic science laboratories were organized in the US in 1932
when J. Edgar Hoover (director of the FBI) opened a national laboratory.
< Performing over 1 million examinations every year, the FBI Laboratory is
the largest in the world, and offers forensic service to all law enforcement
agencies in the U. S. Its accomplishments have won it worldwide
recognition.
< Great Britain has a national system of six regional laboratories that are
under the direction of the Home Office.
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1-3 The Organization of a Crime Laboratory
< Crime laboratory development in the United States has been characterized by rapid growth without national and
regional planning and coordination.
< There are currently about 350 public crime laboratories operate at various levels of government—federal
(national), state, county, and municipal (city).
< With a large diversity of crime laboratories nationwide, it is impossible to use a general model that describes all.
Laboratory staff sizes range from 1 - 100 people, and the services offered can be diverse or specialized.
< There has been an unparalleled growth of crime laboratories in the last 35 years, due to three things:
-- 1) Supreme Court decisions in the 1960's that are responsible for police placing greater emphasis on
scientifically evaluated evidence. The advent of “Miranda Rights” has eliminated confessions as routine
investigative tools.
-- 2) Crime laboratories are inundated with drug and other evidence specimens due to accelerated drug abuse
and increased crime rates.
-- 3) The advent of DNA profiling. Crime laboratories have had to increase staff and laboratory space. DNA
profiling has influenced how the general public perceives modern crime laboratories.
< There are a variety of independent crime laboratories in the United States that precludes (keeps from happening) a
national system. There is no single agency that has unlimited jurisdiction.
< There are four major federal crime laboratories that have been created to assist in cases that extend beyond state
and local jurisdictions. They offer their expertise to any local agency that requests it.
-- 1) The Federal Bureau of Investigation (FBI) maintains the largest crime laboratory in the world.
-- 2) The Drug Enforcement Administration (DEA) are responsible for analyzing drugs seized in violation of
laws.
-- 3) The Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) analyze alcoholic beverages, explosive
devices, weapons, and related evidence.
-- 4) The U.S. Postal Inspection Service is concerned with crimes relating to the postal service.
< Most states maintain crime laboratories to provide service to local and regional agencies that don’t have their own
laboratories.
< Alabama and several other states have a comprehensive statewide system of regional and satellite laboratories.
“Forensic science services are provided from ten (10) laboratories located throughout the state (Huntsville, Florence,
Birmingham/Hoover, Jacksonville, Tuscaloosa, Mobile, Montgomery, Auburn, Dothan, and Calera). The Huntsville,
Birmingham/Hoover, Mobile, and Montgomery Laboratories are programmed as full service or regional laboratories. These
Laboratories form the backbone of the ADFS forensic laboratory system. The five (5) satellite laboratories provide primarily
drug chemistry and crime scene investigation services (Florence, Tuscaloosa, Jacksonville, Auburn, and Dothan). Death
Investigation services are performed in Huntsville, Montgomery, and Mobile medical examiner facilities. Implied Consent
(breath alcohol) services are centralized in Calera. Executive and department-wide administrative activities are performed at
headquarters, in Auburn, as required by law.”
< Statewide systems are operated under a central facility and provide services to most areas of the state.
< Regional laboratories have greatly increased the accessibility of law enforcement agencies to a laboratory while
minimizing duplication of services.
< Local crime laboratories provide services to county and municipal (city) agencies, and are financed by local
government. These operate independently of the state crime laboratories. Most of the larger cities in the U.S.
maintain their own crime laboratories.
< More than 100 countries around the world have created and maintain crime laboratories.
1-4 Services of the Crime Laboratory
< Different crime laboratories have a variety of services due to local laws, the capabilities of the agency, and budget
limitations.
< Many crime laboratories have been created solely for the purpose of processing drug evidence.
< A “full-service” crime laboratory would include the following:
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• Physical Science Unit – Incorporates the principles of chemistry, physics, and geology to identify and compare
physical evidence.
-- May be further divided into Drug Identification, Soil & Mineral Analysis, and Trace Evidence sections.
• Biology Unit – Applies the knowledge of biological sciences in order to investigate blood samples, body fluids,
botanical samples, hair, and fiber samples.
-- Includes DNA profiling
• Firearms Unit – Investigates discharged bullets, cartridge cases, shotgun shells, and ammunition.
-- Also includes comparison of tool marks, tire treads, and shoe prints.
• Document Examination Unit – Provides the skills needed for handwriting analysis and other questioned
document issues.
-- Also analyzes paper and ink, indentations, obliterations, erasures, and burned or charred documents.
• Photography Unit – Applies special photographic techniques for recording and examining physical evidence.
-- Special techniques include digital imaging, infrared & ultraviolet, and X-ray photography.
< Some crime laboratories may offer the optional services of toxicology, fingerprint analysis, voiceprint analysis,
evidence collection, and polygraph administration.
• Toxicology Unit – Examines body fluids and organs for the presence of drugs and poisons.
-- Also responsible for training Breathalyzer operators as well as maintenance of the instruments.
• Latent Fingerprint Unit – Processes and examines evidence for latent fingerprints.
• Polygraph Unit – Conducts polygraph (lie detector) tests, administered by people trained in investigation and
interrogation.
• Voiceprint Analysis Unit – Attempts to tie a recorded voice to a particular suspect.
-- An instrument called a sound spectrograph makes a visual graphic display called a voiceprint.
• Evidence-Collection Unit – Dispatches specially trained personnel to the crime scene to collect and preserve
physical evidence.
< A laboratory’s specialized units must not impede coordination of services for the criminal investigator.
< Forensic investigations requires the implementation of skills from many individuals in many of the units a crime
laboratory has to offer.
1-5 The Functions of the Forensic Scientist
< A forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences to
the analysis of the many types of evidence that may be recovered during a criminal investigation.
< Procedures and techniques used in the laboratory must not only rely on firm science, but must also be admissible in
court.
< The Frye v. United States decision set guidelines for determining the admissibility of scientific evidence into the
courtroom. To meet the Frye standard, the evidence in question must be “generally accepted” by the scientific
community.
< Some courts don’t rely on general acceptance as an absolute prerequisite for acceptance of evidence. The Federal
Rules of Evidence, Rule 702, specifies that “(1) the testimony is based upon sufficient facts of data, (2) the
testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and
methods reliably to the facts in the case.”
< However, in the 1993 case of Daubert v. Merrell Dow Pharmaceutical, Inc., the U.S. Supreme Court asserted that
the Frye standard is not an absolute prerequisite to the admissibility of scientific evidence.
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< Trial judges were said to be ultimately responsible as “gatekeepers” for the admissibility and validity of scientific
evidence presented in their courts, as well as all expert testimony.
< The Daubert Criteria
• In Daubert, the Supreme Court offered some guidelines as to how a judge can gauge scientific evidence:
-- 1) Whether the scientific technique or theory can be (and has been) tested.
-- 2) Whether the technique or theory has been subject to peer review and publication.
-- 3) The technique’s potential rate of error.
-- 4) Existence and maintenance of standards controlling the technique’s operation.
-- 5) Whether the scientific theory or method has attracted widespread acceptance within a relevant scientific
community.
< In the Khumo Tire Co., Ltd. v. Carmichael case, the Court rules that the “gatekeeping” role of the judge applied to
all expert testimony.
< Another case which emphasized that new and unique testing procedures are admissible only if they are based on
scientifically valid principals and techniques is the Coppolino v. State case.
< A forensic scientist may also provide expert court testimony. An expert witness is an individual whom the court
determines possesses knowledge relevant to the trial that is not expected of the average person.
< Trial courts have broad discretion on accepting an individual as an expert witness for any particular subject, but
must ultimately rely on the training and years of experience as a measurement of the knowledge and ability of the
expert.
< The expert witness is called on to evaluate evidence based on specialized training and experience that the court
lacks the expertise to do. The expert will then express an opinion as to the significance of the findings. These views
are only the expert’s opinion and may or may not be accepted by the jury.
< It is impossible for any expert witness to render any view with absolute certainty.
< The competence of a crime lab and its staff is useless if the evidence isn’t properly recognized, collected, and
preserved at a crime scene.
< The forensic laboratory staff must be able to influence the conduct of the crime-scene investigation. This is
addressed by the formation of specialized evidence-collection technicians on 24-hour call.
< The training of a crime-scene investigator must include hands-on training with forensic scientists in addition to
classroom lectures.
< Forensic scientists also participate in training law enforcement personnel in the proper recognition, collection, and
preservation of physical evidence.
Appendix I beginning on Page 543 describes the proper collection and packaging of
common types of evidence. Bookmark this page!
1-6 Other Forensic Science Services
< A number of special forensic science services are available to the law enforcement community to augment the
services of the crime laboratory.
< These services include forensic pathology, forensic anthropology, forensic entomology, forensic psychiatry,
forensic odontology, computer science, and forensic engineering.
• Forensic Pathology – Involves the investigation of unnatural, unexplained, or violent deathsd
-- Forensic pathologists in their role as medical examiners or coroners are charged with determining the cause
of death.
-- The forensic pathologist may conduct an autopsy, which is the medical dissection and examination of a body
in order to determine cause of death.
-- After a human body expires, there are several stages of decomposition:
< Rigor Mortis results in the shortening of muscle tissue and the stiffening of body parts in the position at
death. It occurs within the first 24 hours and disappears within 36 hours. A medical examiner, when
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presented with a body in rogor mortis, can determine that the time since death has been between 24 and 36
hours.
< Livor Mortis results in the settling of blood in areas of the body closest to the ground. It begins
immediately on death and continues up to 12 hours. A medical examiner can determine if a body has been
moved after death.
< Algor Mortis results in the loss of heat by a body. As a general rule, beginning about an hour after death,
the body loses heat by 1 - 1.5 degrees Fahrenheit per hour until the body reaches the environmental
temperature. A medical examiner, when presented with a body, will take the core temperature of the body.
A normal body temperature is around 98.6 EF. If the deceased body has a temperature of around 85.0 EF,
the medical examiner can determine that the time since death was between 9 and 14 hours.
< Potassium levels in ocular fluid (vitreous humor in the eye) also can help to estimate the time since death.
Cells within the eye release potassium at a certain rate, and samples are taken for analysis.
< Other factors, such as the amount of food in the stomach at autopsy can indicate the time period in which
the death occurred.
• Forensic Anthropology – Is concerned primarily with the identification and examination of human skeletal
remains.
-- Skeletal remains are resistant to rapid decomposition and provide many individual characteristics.
-- A forensic anthropologist may also help to create facial reconstructions to aid in indentification.
• Forensic Entomology – Is the study of insects and their relation to a criminal investigation.
-- Insect evidence is commonly used to estimate the time since death.
-- The specific insects present in the body and the stage of development of fly larvae approximate how long the
body has been left exposed.
-- Environmental influences, such as geographical location, climate, and weather conditions must be taken into
consideration.
• Forensic Psychiatry – Is an area in which the relationship between human behavior and legal proceedings is
examined.
-- Forensic psychiatrists are involved in both civil and legal proceedings.
• Forensic Odontology – Involves using teeth to provide information about the identification of victims when a
body is left in an unrecognizable state.
-- Tooth enamel resists decomposition, and outlasts even skeletal remains. The characteristics of teeth are
specific to each individual and can be used for identification.
-- A forensic odontologist also investigates bite marks.
• Forensic Engineering – Is concerned with failure analysis, accident reconstruction, and causes and origins of
fires or explosions.
• Forensic Computer Science – Involves the examination of computers and digital evidence.
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