Introduction to the Forensic Science
Rosamil Rey
FORS 2000
Forensic Science
 Is the application of science to the criminal and civil
laws that are enforced by police agencies in the
criminal justice system.
History and Development of Forensic
Science
 Sir Arthur Conan Doyle’s
Legendary detective
Sherlock Holmes applied
many of the principles of
modern forensic science
long before they were
adopted widely by
police.
Important Contributors
 Mathieu Orfila: (1787-1853) Considered the father of
forensic toxicology. He published he first Scientific treatise
on the detection of poisons and their effects on animals.
 Alphonse Bertillon: (1853-1914) Devised the first
scientific system of personal identification by taking a series
of body measurements as a means of distinguishing one
individual from another.
 Francis Galton: (1822-1911) Undertook the first definitive
study of fingerprints and developed a mythology of
classifying them for filing. His work went on to describe the
basic principles that form the present system of identification
by fingerprints.
 Leone Lattes: (1887-1954) Discovered that blood can be
grouped into different categories, now recognized as A, B,
AB, and O. In 1915, with a simple procedure he determined
the blood group of a dries stain.
 Calvin Goddard: (1891-1955) A U.S. Army colonel,
refined the techniques by using a comparison microscope to
determine whether a particular gun has fired a bullet,
requiring a comparison of the bullet with one that has been
test-fired from the suspect’s weapon.
 Albert
S. Osborn: (1858-1946) Developed the
fundamental principles of document examination and was
accepted as scientific evidence by the courts.
 Edmond Locard: (1877-1966) Persuaded
the Lyons Police Department to give him
two attic rooms and two assistants to start a
police laboratory. Became the founder and
director of the Institute of Criminalistics at
the University of Lyons.
 Locard’s exchange principle: Whenever
two objects come into contact with one
another, there is exchange of material
between them.
Future Challenges
 Since 1900’s, DNA profiling has progressed to the point
at which traces of blood, semen stains, hair and saliva
residues left behind on stamp cups, as well as bite marks,
have made possible the individualization or nearindividualization of biological evidence.
Law of the Institute of Forensic Science – Num. 13
Law of July 24, 1985, as amended.
 IFS was created as an autonomous entity.
 Art. 4. Board Director. (34 LPRA sec. 3002)
 The Director Board created will be responsible for establishing the administrative
and operational policy of the Institute of Forensic Sciences of Puerto Rico. It shall
consist of the Attorney General, who shall preside; by the Commissioner of Public
Safety and Security, by the Rector of Medical Sciences, by the Administrator for
the Courts, by the Secretary of Health and three (3) additional members
appointed by the Governor with the advice and consent of the Senate Puerto
Rico. However, when the Commissioner of Public Safety and Security and the
Superintendent of Police are not the same person, it shall appoint the
Superintendent as an additional member of the Board, given the close working
relationship between the Police and the Institute of Forensic Sciences. These three
(3) members shall be persons of recognized competence, one of whom shall be an
attorney, the other a doctor and the third a private citizen representing the public
interest. The Commissioner of Public Safety and Security, the Rector of Medical
Sciences, the Administrator of the Courts and the Secretary of Health may appoint
a high-level official to represent them at meetings of the Board Director. That
official shall have the same powers for decision-making that has the Chief
Secretary to the Agency or designated in writing. Also that official designee shall
be the same person who attended all the meetings in order to give continuity to
the issues discussed by the Board.
Basic Services in Crime Laboratories
 Biology Unit: staffed with biologists and biochemists who
identify and perform DNA profiling on dried bloodstains and
other body fluids, compare hair and fibers, and identify and
compare botanical materials such as wood and plants.
 Firearms Unit: examines firearms, discharged bullets,
cartridge cases, shotgun shells, and ammunition of all types.
Garments and other objects are also examined to detect
firearms discharge residues and to approximate the distance
from a target at which a weapon was fired.
 Document Examination Unit: studies the handwriting
and typewriting on questioned documents to ascertain
authenticity and/or source. Related responsibilities include
analyzing paper, ink, obliterations, erasures and burned or
charred documents.
 Photography
Unit: examines and records physical
evidence. Highly specialized procedures include digital
imaging, infrared, ultraviolet and x-ray photography. This
unit also prepares photographic exhibits for courtroom
presentations.
 Toxicology Unit: examines body fluids and organs to
determine the presence or absence of drugs and poisons.
 Latent Fingerprint Unit: processes and examines
evidence for latent fingerprints when they are submitted in
conjunction with other laboratory examinations.
 Polygraph Unit: the lie detector has been recognized as an
essential tool of the criminal investigator rather than forensic
scientist.
 Crime Scene Investigation Unit: collect and preserve
physical evidence that will later be processed at the crime
laboratory.
Functions of the Forensic Scientist
 Analysis of Physical Evidence
 The forensic scientist must be skilled in applying the principles
and techniques of the physical and natural sciences to analyzing
the many types of physical evidence that may be recovered
during a criminal investigation.
• The Importance of Physical Evidence
 Science derives its integrity from adherence to strict guidelines
that ensure the careful and systematic collection, organization,
and analysis of information – scientific method.
 The underlying principles of the scientific method provide a
safety net to ensure that the outcome of an investigation is not
tainted by human emotion or compromised by distorting,
belittling, or ignoring contrary evidence.
 Determining Competence
 In order to allow experts share their investigation in court,
competency may be established by having him or her cite
educational degrees, participation in special courses, and
membership in professional societies.
 The testimony must arise from personal knowledge, they’re
called upon to evaluate evidence when the court lacks the
expertise to do so.
 The forensic scientist should not be an advocate of one’s party
cause, but only an advocate of the truth. Later the duty of the
judge or jury is to weigh the pros and cons of all the
information presented in deciding guilt or innocence.
Other Forensic Science Service
 Forensic Psychiatry
 Specialized area in which the relationship between human
behavior and legal proceedings is examined. In civil cases, they
determine whether people are competent to make decisions
about preparing wills, settling property, or refusing medical
treatment. In criminal cases, they evaluate behavioral disorders
and determine whether people are competent to stand trial.
 Forensic Odontology
 Help identify victims when the body is left in an unrecognizable
state. Teeth are composed of enamel, the hardest substance of
the body. With the use of dental records, dental casts or even
photographs of the person’s smile, a set of dental remains can be
compared to a suspected victim.
 Forensic Engineering
 Concerned with failure analysis, accident reconstruction and
causes and origins of fire or explosions. Accident scenes are
examined, photographs are reviewed, and any mechanical
objects involved are inspected.
 Forensic Computer and Digital Analysis
 Involves the identification, collection, preservation, and
examination of information derived from computers and other
digital devices, such as cell phones. It normally involves the
recovery of deleted or overwritten data from a computer’s hard
drive and the tracking of hacking activities within a
compromised system.
Application and Critical Thinking
Police investigating an apparent suicide collect the
following items at the scene:
1.
A note purportedly written by the victim
b) A revolver bearing very faint fingerprints
c) Traces of skin and blood under the victim’s fingernails
What unit of the crime laboratory will examine each piece of
evidence?
a)
2.
List at least three (3) advantages of having an evidence
collection unit process a crime scene instead of a patrol
office or detective.