Terms and jargon
used in Forensic Pathology
Accelerant
A substance that is used to create and sometimes
direct the spread of a fire. The most commonly
used liquid accelerants include gasoline,
lighter fluid, kerosene, and turpentine. See
Gas Chromatography for information on how
accelerants are identified.
Accident Reconstruction
The use of physical evidence to build a theoretical
model of a given crime or accident scene.
Adipocere
A waxy, soap-like substance formed during
the decomposition of bodies buried in moist
places. It consists principally of insoluble
salts of fatty acids. Also called "grave
wax." Composed of oleic, palmitic, and
stearic acids.
Allele
Any of several alternative forms of a gene
located at the same point on a particular
pair of chromosomes. For example, the genes
determining blood types A and B are alleles.
Anthropology
The science of the origin, culture, and development
of humans. This can come into play when identifying
skeletal remains, certain foodstuffs or items
of clothing.
Antibody
A protein that destroys or inactivates a
specific antigen. Antibodies are found in
the blood serum.
Antigen
A substance, usually a protein, that stimulates
the body to produce antibodies against it.
Arson
The crime of intentionally setting fire to
buildings and other property.
Aspermia
The absence of sperm. Sterility in males.
Autopsy
The internal examination of a body after
death; performed to confirm or determine the
cause of death.
Autorad
Common term for "Autoradiograph,"
the final product in a DNA analysis. Autorads,
which look very much like bar-codes, are formed
by the reaction of electricity with genetic
material (DNA). This reaction is unique to
each sample of genetic material, providing
an invaluable tool for identification. The
reaction takes place on a nylon membrane which
is photographed against x-ray film.
Ballistics
The science of the motion of projectiles.
When a bullet is fired, it will have distinctive
characteristics caused by the gun from which
it is fired. Examiners can use this evidence
to match bullets or bullet fragments to specific
weapons.
Blood Spatter
The impact of spilled blood on surfaces.
The pattern of the impact can provide vital
information about the source of the blood.
Blood spatter can help determine the size
and type of wounds, the direction and speed
with which the perpetrator or victim was moving,
and the type of weapons used to create the
blood spill.
Blood Volume Test
A test designed to show the quantity of blood
shed in a particular area. Also designed to
show how much blood was shed to create a given
stain or blood spatter pattern, and the amount
of time needed to create that stain.
Bloodstain Interpretation
The interpretation of size, shape, orientation,
and distribution of bloodstains on various
surfaces, and what information can be derived
from the proper interpretation of the stains.
Botany
The scientific study of plants. Plant matter
found at crime scenes is organic material
and, like bodily fluids, has unique DNA sequences.
Bullet Track
The path of a bullet or projectile as it
passes through matter, such as a body or a
wall.
Caliber
The diameter of the bore of a rifled firearm,
usually expressed in hundredths of an inch.
Cast-off Blood
Blood that travels from a source due to the
movement of that source. A bleeding person
will cast-off blood, as will a weapon or other
item that is in movement.
Cast-off Trails
The patterns that are created by cast-off
blood.
Catalyst
A substance that accelerates the rates of
chemical reactions but is not itself permanently
changed by the reaction.
Cause of Death
Any injury or disease that results in physical
trauma to the body, leading to death. Medical
Examiners and/or Coroners will make the determination
of cause, either at the scene or during a
subsequent autopsy.
Centers for Disease Control (CDC)
Atlanta-based US government institution whose
mission is to study and prevent disease in
human and animal populations.
Chromosome
A rod-like structure in the nucleus of a
cell along which genes are located.
Clinical Forensic Nursing
The application of clinical nursing practice
to trauma survivors or to crime victims, involving
the identification of the unrecognized, unidentified
injuries, and the proper processing of forensic
evidence
Composite Drawing
A sketch of a suspect produced from eyewitness-descriptions
of one or more persons.
Computer Forensics
The application of computer technology for
the purpose of examining potential evidence,
including, but not limited to: theft of trade
secrets; theft of, or destruction of property;
and fraud. Specialists can recover data that
has been deleted, encrypted, or damaged.
Crime Scene Staging
The attempt by a perpetrator or accomplice
to alter a crime scene in order to reduce
its evidentiary value.
Criminal Profiling
A tool used to aid investigators by providing
information about the type of individual committing
a specific crime. Information taken from the
crime scene is integrated with known psychological
theory and the history and background of the
victim to draw up a biographical sketch of
the perpetrator.
Criminology
The study of criminal activity and how it
is dealt with by the law.
Diatom
A microscopic, single-cell form of marine
or fresh-water algae, having siliceous cell
walls. A body of water may contain many specifies
of diatoms, but not all species of diatoms
live in every body of water. Through painstaking
examination, forensic scientists are able
to identify the body of water wherein a given
specifies of diatom lives.
DNA
Deoxyribonucleic Acid. Constructed of a double
helix, DNA is the genetic material contained
in cells. All organic matter has a specific
DNA sequence; these sequences act like a genetic
fingerprint and are currently the best method
for identifying organic evidence like blood
and other bodily fluids.
DNA Databanks
Databases which store DNA profiles collected
from various classes of offenders. DNA from
a given crime can be entered into the databank;
it can then be matched with DNA profiles from
other crimes, providing potential matches
from previous convictions.
DNA Profiling
The process of testing to identify DNA patterns
or types. In forensic science this testing
is used to indicate parentage or to exclude
or include individuals as possible sources
of bodily fluid stains (blood, saliva, semen)
and other biological evidence (bones, hair,
teeth.)
Electrophoresis
A technique by which DNA fragments are placed
in a gel and charged with electricity. The
process separates the fragments by size, as
part of the process of creating a genetic
profile.
Endothermic Reaction
A chemical transformation in which heat energy
is absorbed from the surroundings.
Entomology
The scientific study of insects. The type
of insects and their state of development,
in combination with weather data and the condition
of a decomposing body, can provide forensic
investigators with accurate indicators of
time of death.
Epidemiology
The study of the occurrence, distribution,
and causes of disease in human and animal
populations.
Epilepsy
A group of neurological disorders characterized
by recurrent episodes of convulsive seizures,
sensory disturbances, abnormal behavior, loss
of consciousness, or all of these.
Evidence
Anything that has been used, left, removed,
altered, or contaminated during the commission
of a crime.
Fingerprint
The unique patterns created by skin ridges
found on the palm sides of fingers and thumbs.
Fluoresce
When a substance emits visible light when
exposed to light of a shorter wavelength.
Ultraviolet light, for example, will cause
many objects to fluoresce.
Forensic Animation
The use of video technology to recreate crime
scenes. Forensic animations are sometimes
entered into evidence so jurors can view a
sequence of events that otherwise could only
be described by opposing attorneys. Some courts
will not admit forensic animation into trial..
Forensic Linguistics
The forensic analysis of language such as
letters, confessions, threats, and recorded speech.
Forensic Linguistics Demographics
The analysis of language to reveal traits of
the speaker or writer such as possible geographic origin,
education level, or occupation.
Forensic Meteorology
The study of weather patterns and how they
relate to the investigation of crimes.
Forensic Psychologist
A trained mental health professional who
examines suspects, perpetrators and victims
in order to establish their psychological
state and their ability to participate in
the legal process.
Forensic Pathology
The study of how and why people die; a sub-specialty
of pathology.
Forensic Science
The application of science to law and the
investigation of criminal activity.
Forensic Sculpting
The attempt by a sculptor to create a likeness
of a given individual using his or her skull.
Gene
A unit of inheritance located on a chromosome.
Genetic Fingerprinting
See DNA. The use of DNA technology to identify
given individuals.
Geographic Profiling
A method to help investigators locate serial
offenders. The sites and times of serial crimes
in a given jurisdiction are entered into a
computer program. This program then processes
the information to give investigators a hypothetical
area in which the perpetrator lives and operates.
Gas Chromatograph (GC)
A forensic tool used to identify the chemical
makeup of substances used in the commission
of crimes. The questioned substance is burned
at high temperatures. The temperature at which
this material becomes gas is then charted
to determine its makeup.
Hemoglobin
A red blood cell protein responsible for
transporting oxygen in the bloodstream. Also
provides the red coloring of blood.
High Explosive
Any explosive with a velocity of detonation
greater than 1000 meters per second. Dynamite
is a high explosive.
Idiolect
The variety of a language unique to an individual.
Inorganic Compound
A chemical compound not based on carbon.
Laser
Stands for Light Amplification by Stimulated
Emission of Radiation. A device that produces
a coherent beam of optical radiation by stimulating
electronic, ionic, or molecular transitions
in order to create energy.
Latent Fingerprint
A fingerprint made by deposits of oils and/or
perspiration, not usually visible to the human
eye. Various technologies, including lasers,
can be used to identify latent prints.
Lie Detector
Also known as a "Polygraph." A
machine that charts how respiration and other
bodily functions change as questions are asked
of the person being tested. An attempt to
knowingly provide false answers can cause
changes in bodily functions. Lie detector
tests are not admissible in court.
Limnology
The study of fresh waters (lakes and ponds
-- both natural and manmade) is including
their biological, physical, and chemical aspects.
Lividity
Also known as "liver mortis." Postmortem
discoloration caused by the gravitation of
blood to various parts of the body. Can be
used to help determine time of death, and
placement of a body after death.
Low Explosive
An explosive with a velocity of detonation
less than 100 meters per second. Gunpowder
is a low explosive.
Luminol
A chemical that is capable of detecting bloodstains
diluted up to 10,000 times. Luminol is used
to identify blood that has been removed from
a given area. It is an invaluable tool for
investigators at altered crime scenes.
M.O., or ‘Method of Operation’
From the Latin, Modus Operandi. Refers to
method by which crimes are committed. Most
often used on an individual basis to establish
the pattern with which a perpetrator carries
out a crime or series of crimes.
Manner of Death
An explanation of the way in which death
is caused. Medicolegal manners of death are:
homicide, suicide, accidental, natural, and
undetermined.
Medical Examiner
A medical doctor who determines causes of
death, performs autopsies, and acts as an
expert witness in criminal and civil trials
where cause and/or manner of death are relevant.
Micro-spectro Photometry
The use of an electronic microscope in which
electrons are beamed onto the specimen. The
analyst then charts the electron emissions
that are created in order to identify the
specimen.
Mitochondrial DNA (mtDNA)
A short sequence found outside of the cell
nucleus in cells. Called mitochondria, this
material is used in the absence of quality
genetic material like blood, semen or saliva.
It is passed only from mother to child; siblings
share maternal mitochondria. Hairs and fingernails
are good sources of mitochondria.
Monochromatic Light
Light having a single wavelength or frequency.
Narcotic
Analgesic or pain-killing substance that
depresses vital body functions such as blood
pressure, pulse rate, and breathing rate.
Odontology
The study of the anatomy, growth, and diseases
of the teeth. In the absence of other factors,
ondontolgy can be used to identify human remains.
Orthotolidine Solution
A chemical solution that will determine whether
a given stain contains blood.
Ouchterlony Test
A test that determines if a blood stain is
human or animal.
Palynology
The study of pollens.
Pathology
The study of the essential nature of diseases
and especially of the structural and functional
changes produced by them.
Perspective Analysis
In order to determine the size of objects
within a given photograph, analysts will identify
one item in that photograph and measure the
distance between that item and the camera
used to make the photograph. This perspective
allows them to measure everything in the photograph.
Petechial Hemorrhage
Small, pin-like hemorrhages that occur beneath
the skin. Usually observed on the lining of
the inner surface of the eyelids. This is
a common result of death by asphyxiation or
strangulation.
Photograph Analyst
A specialist who breaks down photographic
images to identify suspects and to measure
items and people within those images.
Physical Evidence
Any object that can establish that a crime
has been committed, or can provide a link
between a crime and its victim, or between
a crime and its perpetrator.
Point-by-Point Analysis
When comparing a known object to one that
needs to be identified, analysts will break
down photos of each into small quadrants,
and compare the respective similarities within
those quadrants.
Polymerase Chain Reaction (PCR)
Scientists often refer to PCR as "photocopying
DNA," since it allows them to rapidly
replicate DNA molecules. The technique usually
is employed when a given sample of DNA is
too small for forensic testing.
Psychological Profile
A tool used to aid investigators by providing
speculative information about a perpetrator’s
psychological makeup. Information from crime
scenes is integrated with psychological theory
and then cross-referenced against similar
crimes. The result is a hypothetical model
of the suspect that can include age, occupation,
appearance, and personal information ranging
from sexual preferences to dietary habits.
Psychopathic Personality
A person whose behavior is largely amoral
and asocial, and who is characterized by perverse
or impulsive behavior, and a lack of remorse
for the consequences of this behavior.
Puncture Wound
A wound that is neither an impact wound nor
one caused by a projectile; a piercing of
the body, usually by a handheld object.
Questioned Documents
Any object that contains handwritten or typewritten
markings whose source or authenticity are
not known, but which is still relevant to
the outcome of a legal proceeding.
Rape Kit
Biological material collected from a rape
victim after the fact, to obtain genetic material
of the suspected perpetrator.
Restriction Fragment
Length Polymorphisms (RFLP)
Length differences associated with strands
of DNA. These differences vary from person
to person, thus providing a means to further
identify DNA.
Reverse Paternity DNA
A method by which a person’s blood
can be identified by comparing the DNA profiles
of individuals believed to be that person’s
parents. Individual DNA makeup is a combination
of parental DNA. Siblings will share these
patterns while retaining unique DNA markers.
Ridge Characteristics
Ridge endings, bifurcations, enclosures,
and other ridge details, which must match
in two fingerprints for their common origin
to be established.
Secretor
An individual who secrets his or her blood-type
antigen(s) in bodily fluids. Before DNA technology,
blood type from bodily fluids other than blood
could only be obtained from secretors, who
make up about 80 percent of the population.
Serology
A technology dealing with the properties
and actions of serums in blood; also known
as "blood analysis." This was the
preferred
method of typing blood before the advent of
DNA.
Serum
The liquid that separates from the blood
when a clot is formed.
Spectrograph
A technology that measures how a given object
responds to frequencies within the light spectrum.
Objects can be identified and their properties
visually clarified by use of this technology.
Sublimation
A physical change from a solid directly into
a gaseous state.
Super Glue Fuming
Techniques used to develop latent fingerprints
on non-porous surfaces. A chemical in the
glue reacts with and adheres to the finger
oils, and then expose latent prints.
Toxicology
The study of poisons and drugs and their
effect on human and animal populations.
Trace Evidence
Material deposited at a crime scene that
can only be detected through a deliberate
processing procedure. An individual enteringany
environment will deposit traces of his or
her presence, and this material can be used
as evidence. Common sources of traceevidence
are hairs and fibers.
