Below is a list of forensic terms that are commonly found in case reports and general ADFS language. For a more complete forensic
terms list, please refer
to this glossary.
Absolute Certainty - ultimate sureness with no implication of
Accountability - the quality of subordinate workers being
responsible for his/her own work and answerable to a superior.
Accuracy - the degree of conformity of a measured quantity to
its actual (true) value.
Acetone - a colorless, highly flammable chemical compound used
as an organic solvent, an ingredient in many lacquer thinner compounds and
Accelerant - an agent, often an ignitable liquid, that acts to
initiate a fire or increase its rate of spread.
Administrative documentation - records such as case related
conversations, evidence receipts, description of evidence packaging and seals,
and other pertinent information.
Administrative (or Laboratory Director) Case File Review - a
detailed final review of the case file documentation. A member other than the
assigned analyst must conduct the Laboratory Director case file review on all
Algor mortis - the postmortem cooling of the body.
Analytical Data - all case specific records such as notes,
worksheets, graphs, spectra, printouts, computer data files, photographs,
photocopies, microscopic slides and other data or records.
Analytical Procedure - an orderly step-by-step process designed
to ensure operational uniformity and to minimize systematic variability.
Analyst - any ADFS personnel assigned to perform scientific
investigation or evidential examination.
Ante mortem – preceding death Antigens - foreign substances in
the body that are capable of causing disease.
Arson - the intentional and unlawful burning of a building or
Assessment - the process of evaluating analysts to determine
their level of technical knowledge, skills, and abilities.
Asphyxiation - a medical term for suffocation, which leads to
lack of oxygen in the blood.
Audit - a review conducted to compare the various aspects of
the laboratory’s performance with a standard for that performance.
Back spatter - blood directed back toward the source of energy
or force that caused the spatter; often associated with entrance gunshot wounds.
Ballistics - branch of physics that deals with the flights of
Base pair - combination of 2 nucleotides (A and T or G and C)
held together by weak hydrogen bonds; the DNA double helix is formed when a base
pair of nucleotides in the DNA strands are connected by these bonds.
Bile - a digestive fluid made by the liver and stored in the
gallbladder that helps digest fats.
Biology – the science that studies living organisms.
Blind or Double-Blind Sample Technique - a type of proficiency testing where the
member is not aware that the sample/case under analysis is a quality assessment
Blood borne pathogens - pathogenic microorganisms in blood or other body fluids
that can cause disease in people. These pathogens include, but are not limited
to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV) in all of its
Bloodstain - transfer resulting when liquid blood comes into contact with a
Calibration - the set of operations which establish, under specified conditions,
the relationship between values indicated by a measuring instrument or measuring
system, or values represented by a material, and the corresponding known values
of a measurement.
Case File – the hard copy case folder which contains all or part of the
documentation forming the case record.
Case Record - all notes, reports, custody records, charts, analytical data, and
any correspondence generated in the laboratory pertaining to a particular case,
which may be located in the hard copy case folder or the LIMS.
Case Management - the approach for setting up a logical methodology for
acceptance, analytical work, priority, transfer, and return related to work
Cause of death - disease or injury that initiates the lethal train of events
leading to death.
Cerebral edema – the presence of a large amount of water in the spaces of the
Certificate of Analysis - a document that reports and certifies the test results
of a product.
Certified Reference Material - a reference material or standard whose property
values are certified by a valid procedure or are accompanied by or traceable to
a certificate or other documentation is issued by a recognized certifying body.
Chain of Custody - a record of individuals who have had physical possession of
Chemicals & Toxic Substance List - a list of recognized chemicals and toxic
substances present in the laboratory facilities.
Chromatogram - the pattern of separated substances obtained by chromatography.
Chromatography - a method for separating mixtures based on differences in the
speed at which they migrate over or through a stationary phase.
CODIS - Combined DNA Index System; a DNA database system
CODIS administrator - an employee of the laboratory responsible for
administration and security of the laboratory’s CODIS at a laboratory that owns
the database and/or known samples.
Competency test - the evaluation of a person’s ability to perform work in any
functional area prior to the performance of independent casework.
Congenital anomaly - an abnormality, such as a spinal column defect, present at
Contact wound - a skin injury produced by a weapon in contact with or a fraction
of an inch from the skin when discharged.
Continuing Education Courses - short, defined periods of formal job-related
instruction (including but not limited to professional meetings) provided to
members of a Forensic Laboratory for the purpose of enhancing job knowledge,
skills, or abilities. Documentation of such training is to be kept on file in
the Quality Manager’s Office.
Control - a test with predictable results performed with an experimental
procedure to confirm the reliability of the experimental results.
Controlled Substance – a drug or chemical whose manufacture, possession, and use
are regulated by a government.
Coroner - an elected official with death investigation duties.
Corroborating evidence - evidence that tends to support a proposition that is
already supported by some evidence.
Crime/Forensic Laboratory - a laboratory (with at least one full-time
scientist), which examines physical evidence in criminal matters and provides
opinion testimony with respect to such physical evidence in a court of law.
Crime scene - an area, object or person, external to a laboratory facility, from
which evidence is identified, documented, collected, and/or interpreted.
Criteria - standards against which compliance is evaluated. The criteria are
used to evaluate whether the laboratory activity meets the standard. This is
often a restatement of the standard in the form of a question which can be
answered “yes”, “no”, or not applicable – “(N/A)”.
Database - refers to the DNA analysis of database samples for entry into CODIS
and, if eligible, for upload to the National DNA Index System (NDIS).
Database sample - a sample obtained from an individual who is legally required
to provide a DNA sample for databasing purposes and whose identity is
established at the time of collection of the sample.
Deficiency - an inadequacy or lacking in some necessary defined quality or
element. Deficiencies include but not limited to missing data, incomplete data,
or incomplete reports.
Desirable - a defined standard, which has the least deleterious effect on the
work product or the integrity of the evidence but which nevertheless, enhances
the professional status, character, or values of the laboratory.
Detection Limit - the lowest quantity of a substance that can be distinguished
from the absence of that substance (a blank value) within a stated confidence
Discipline - a major forensic science area dealing with similar tests,
examinations, or comparisons. Examples include but are not limited to the
disciplines of DNA Database, Drug Chemistry, Firearms/Toolmarks, Forensic
Biology, Forensic Pathology/Death Investigation, Implied Consent, Scene
Investigation/Processing, and Toxicology.
Discipline Standard Operating Procedures Manuals (SOP) - manuals that
concentrate on issues that are unique to a discipline or functional area.
Examples include but are not limited to: maintenance and calibration of
instruments and balances; reference standards and controls; detailed analytical
protocols and procedures; health and safety issues specific to functional area.
Each Discipline or Functional Area is required to have a Discipline SOP Manual.
Discrepancy - any reported result, casework, or proficiency test, which differs
from the consensus result. Discrepancy is also defined as an apparent error in
the final conclusion from an analytical procedure. Analytical procedures are
tests performed in casework and proficiency tests. A final conclusion is issued
in a report after appropriate reviews. Discrepancies may be classified as Class
I, II, or III.
Deoxyribonucleic Acid (DNA) - a nucleic acid that contains the genetic
instructions used in the development and functioning of all known living
organisms and some viruses.
Drift, Analytical - the systematic or scientific variability in a method, test,
or procedure where results gradually deviate from the norm or the expected
Drug Chemistry Section - the discipline responsible for the analyzes of any
substance seized under the state’s laws restricting the sale, manufacture,
distribution and use of abusive-type drugs.
Drug Standards Inventory - the physical accounting of drug standards used in the
Chemistry and Toxicology Sections.
Duty - a responsibility, task, etc., required by or relating to one’s occupation
Electrophoresis - a technique for the separation of charged molecules by
migration on a support medium under the influence of an electrical charge.
Equivocal death - manner of death (homicide, suicide, accident) remains
undetermined after a complete investigation.
Error Rate - the frequency at which one deviates or strays from a correct
Essential - a defined standard, which directly effects and has a fundamental
impact on the work product of the laboratory or the integrity of the evidence.
Evidence - any item entrusted to the ADFS Forensic Laboratories for
Evidence Inventory - the physical accounting of evidence and records related
Evidence Submission Form - form used to receive evidence into the laboratory and
to initiate request for laboratory examinations or analyses.
Evidence Transfer - a change in the possession of a custody item that must be
documented in two specified locations (submitter and receiver). Transfers can
occur from person to person, person to secure place, or secure place to secure
Evidence Vault(s) - a secured room or rooms for the storage of custody items.
Examinations (Training) - objective evaluative instruments designed to measure
job-related knowledge, skills or abilities and usually conducted in one or more
of these formats: written, oral, practical or moot court.
Examinations (Evidential) - the questioning, testing, comparing, or analyzing of
a custody item in a prescribed manner that is helpful in forming a conclusion or
judgment relative to the item
Exception - the temporary suspension of some essential element of a policy,
procedure, or requirement caused by circumstances that are expected to return to
normal at some point in the future. For the duration of the period, the policy,
procedure, or requirement is temporarily modified. If the period is anticipated
to last longer than one year, then the modification should be incorporated into
the ADFS Quality or Operations manual.
External Proficiency Test - an exam process/instrument prepared by an outside
provider and used as a quality assessment sample.
Exsanguination - bleeding to death.
False negative – test result that states that an analyte is absent, when, in
fact, it is present above the established limit of detection for the analyte in
False positive – test result that states that an analyte is present, when, in
fact, it is not present or, is present in an amount less than a threshold or
designated cut-off concentration.
Fire Debris - a general term used to define the debris from a fire that is
collected as evidence for laboratory examination.
Firearms and Toolmarks Section – a discipline responsible for the comparison of
firearms, casings, projectiles and other evidence that may be associated through
toolmarks. Toolmarks result whenever two items come into contact with sufficient
force, such that one or both of the items bear markings resulting from the other
Forensic - the application of scientific knowledge to legal problems.
Forensic biology - the application of biology to law enforcement.
Forensic Pathology - a branch of pathology concerned with determining the cause
of death by examination of a corpse.
Forensic science - the process of using science to resolve legal issues.
Forensic Toxicology - a discipline of forensic science concerned with the study
of toxic substances or poisons, of which there are many thousands.
Gas chromatography - gas flowing through a coated tube separates compounds by
their size, weight, and chemical reactivity with the coating of the tube or
Gel - support medium (agarose) that holds DNA molecules in place during the
separation phase of electrophoresis.
Genetics - the study of inherited traits, genotype/phenotype relationships, and
population/species differences in allele and genotype frequencies.
Goal - a statement of purpose defining the mission or intended outcome.
Good Analytical Practice - approved method to perform a specific analytical
technique that influences the quality of the analysis.
Good Laboratory Practice - an approved method to perform a basic operation,
activity, or service in a laboratory which influences or enhances the quality of
Histology - is the anatomical study of the microscopic structure of tissues.
Hypostasis - the pooling of blood as it accumulates at the lowest parts of the
body, being pulled down by gravity; is a method of determining the position of
the body at/after death.
Hypothermia - this situation occurs when the core temperature of one's body
falls below normal. It is the failure of the body to maintain adequate
production of heat under conditions of extreme cold.
IBIS (Integrated Ballistics Information System) - a database used for acquiring,
storing, and analyzing images of bullets and cartridge casings. Important - a
defined standard, that is considered to be a key indicator of overall quality in
the laboratory, but which may not directly affect the work product or the
integrity of the evidence.
Inspection - a review or audit of areas, practices, procedures for compliance
with existing policy.
Inventory - a detailed accounting of all items within a specified location.
Examples include but are not limited to: evidence in the evidence vault,
evidence in the possession of an analyst, drug standards in the secure storage
area for drug standards, contents of a container, etc.
Internal Proficiency Test - an exam process/instrument originating from within
the laboratory system and used as a quality assessment sample.
Known sample - biological material whose identity or type is established. An
example of a known sample is a sample contributed by the close biological
relative of a missing person.
Known Standard - a specimen from an identified source acquired for the purpose
of comparison with the evidence.
Laboratory - a facility (1) employing at least two full-time employees who are
qualified DNA analysts and (2) having and maintaining the capability to perform
the DNA analysis on database and/or known samples at that facility.
Laboratory Director (or Administrative) Case File Review - a detailed final
review of the case file documentation. A member other than the assigned analyst
must conduct the Laboratory Director case file review on all case files.
Laboratory Personnel - ADFS members with specific laboratory responsibilities.
Laboratory Satellite - a member of a laboratory system that is managed by, but
is physically separated from, a parent or regional laboratory.
Laboratory System - an organization containing at least two physically separate
laboratory facilities that are independently managed under the control of a
single superior in the chain of command.
Laboratory support personnel - employees who perform laboratory duties exclusive
of analytical techniques on database and/or known samples.
Lacerations - anything that has been torn roughly for example - a rough cut.
Limited Access - access limited to personnel authorized by the laboratory
Manner of death - death occurs in one of four manners: natural, if caused solely
by disease; accidental, if it occurs without apparent intent; suicide, if caused
by the deceased; homicide, if someone other than the deceased caused it.
Mass spectrometers - an instrument used to both measure and analyze molecules
under study. The process involves introducing enough energy into a target
molecule to cause its ionization and disintegration. The resulting fragments are
then analyzed, based on the mass to charge ratio and produces a "molecular
Mass spectrometry - this technique can be used to both measure and analyze
molecules under study. It involves introducing enough energy into a target
molecule to cause its ionization and disintegration. The resulting fragments are
then analyzed, based on the mass/ charge ratio to produce a "molecular
Medical Examiner - government official, always a physician and often a forensic
pathologist, charged with investigating sudden and unexpected deaths or deaths
Method - the course of action or technique followed in conducting a specific
analysis or comparison leading to an analytical result.
NDIS - The National DNA Index System. NDIS is one component of CODIS—the
national and highest-level index containing the DNA records contributed from
participating federal, state, and local laboratories.
Notes - the documentation of procedures, standards, control and instruments
used, observations made, results of tests performed, charts, graphs,
photographs, sketches and other documents generated that are used to support the
Objective - a measurable, definable accomplishment that furthers the goals of
Offender - An individual who is required by statute to submit a sample for DNA
analysis and databasing. The term “offender” includes individuals who are
convicted of or arrested for a crime or juveniles adjudicated delinquent for an
offense and required by state or federal law to provide a DNA sample for
analysis and databasing.
Open Proficiency Test - an exam process/instrument where the analyst is aware
that the sample is a proficiency test.
Operations Manual - a document stating procedures and protocols dealing with the
day-to-day issues of ADFS business that does not deal directly with evidence or
Peer - an individual having expertise in a specific functional area or
discipline gained through documented training and experience.
Performance Audits - the review of laboratory administration, management,
sections and/or analysts for compliance with policies, procedures, and
operational effectiveness outlined in the ADFS Departmental Quality Manual.
Policy - a guiding principle, operating practice, or plan of action governing
decisions made on behalf of an organization.
Population – the totality of items or units of material under consideration.
Principle - a basic rule, assumption or quality; a fixed or predetermined policy
or mode of action.
Probability - the ratio of the number of outcomes in an exhaustive set of
equally likely outcomes that produce a given event to the total number of
Procedure - An established practice to be followed in performing a specified
task or under specific circumstances.
Process Development - the act of defining and describing a process. It may
include planning, architecture, design, implementation, and validation.
Proficiency Test - a process to evaluate the competence of an analyst/laboratory
by evaluation of the results obtained on test materials. Involves the use of
open, blind, reexamination, or known sample techniques.
Property Inventory - the physical accounting of capital equipment.
Protocol - a directive listing the procedures to be followed in performing a
particular laboratory examination or operation. Also refers to the overall plan
for analysis of a particular type of evidence.
Postmortem - after death
Proper seal - a seal that prevents loss, cross-transfer, or contamination while
ensuring that attempted entry into the container is detectable. A compliant seal
may include a heat seal, tape seal, or a lock with the initials of the person
creating the seal being placed on the seal or across the seal onto the container
Pulmonary Edema – an abnormal buildup of fluid in the air sacs of the lungs.
Qualifying Test - measures proficiency in both technical skills and knowledge.
Also known as Competency Test.
Quality - the degree of excellence achieved by laboratory through its work
Quality Assessment - the overall system of activities designed to provide
assurance that quality control activities are effective.
Quality Assurance - those planned and systematic actions necessary to provide
sufficient confidence that a laboratory’s product or service will satisfy given
requirements for quality.
Quality Audit - a management tool used to evaluate and confirm activities
related to quality.
Quality Control - internal activities, or activities conducted according to
externally established standards, used to monitor the quality of analytical data
and to ensure that it satisfies specified criteria.
Quality Manual - a document stating the quality policy and describing the
various elements of the quality system and quality practices of the laboratory
system. The Forensic Science Quality Manual is the “ADFS Departmental Quality
Quality Manager - the individual designated by top management having authority
and responsibility to ensure that the requirements of the ADFS quality system
are implemented and maintained.
Quality System - the organizational structure, responsibilities, procedures,
processes, and resources for implementing quality management
Qualitative analysis - determination of the identity of a substance.
Random - 1) having no specific pattern 2) produced by chance or unplanned in
Reliability - the extent to which an experiment, test or measuring procedure
yields the same the same results on repeated trials.
Reagent - a substance that, because of the reactions it causes, is used in
analysis and synthesis.
Reagent blank control - an analytical control sample that contains no template
DNA and is used to monitor contamination from extraction to final fragment or
sequence analysis. This control is treated the same as, and parallel to, the
database, known, or casework reference samples being analyzed.
Re-Examination Technique - exhibits (the questioned and known items of original
evidence) of a previously analyzed case are examined and a conclusion reached by
the reviewer, prior to the reviewer knowing the analysts’ conclusions.
Reference Standard - a sample acquired or prepared that has known properties for
the purpose of calibrating equipment and/or for use as a control in experiments
Reliability - the quality of being dependable. May refer to personnel,
materials, reagents, methods, and equipment.
Retinal Hemorrhage - Abnormal bleeding of the blood vessels in the retina, the
membrane in the back of the eye.
Rigor mortis - Stiffening of the body after death; a time dependent change that
helps determine time of death.
Root Cause Analysis - the process of determining the underlying cause of a
problem which might warrant corrective action. A root cause analysis is not a
simple re-statement of what is wrong, but is a process of repeatedly asking
probing questions about what went wrong, obtaining answers, and asking questions
about the answers until the underlying cause of the problem is determined.
Problems tend to recur unless the root cause is determined and corrected.
Report - an official record of information relating to investigations and
analyses conducted by ADFS or other parties. Reports are generated for casework
and proficiency testing examinations. Casework reports are normally generated
using the LIMS format, while proficiency test reports may be prepared and
distributed according to policies set by individual ADFS disciplines.
Rule - an authoritative direction for conduct or procedure.
Safety & Security Inspections - the review or audit of procedures and equipment
to ensure the safety and security of laboratory personnel and facilities
Scene - an area, object, or person external to the examining forensic laboratory
facility, from which evidence is identified, documented, collected, and/or
Science - A systematic gathering of knowledge. The observation, identification,
description, experimental investigation and the theoretical explanation of
Scientific method - Procedures for the systematic gathering of knowledge. These
procedures generally involve:
- state the problem
- develop a hypothesis
- test the hypothesis
- form a theory
- use theories to predict events
- theory becomes law
Scientist - One learned
in science and esp. natural science.
Section Evidence Area - a secured room or
cabinet for temporary storage of evidence by analysts.
Secure area - a locked
space (for example, cabinet, vault or room) with access restricted to personnel
authorized by the laboratory director.
Seminal - pertaining to or containing or
consisting of semen; "seminal fluid".
Serology - a sub-discipline of biology,
which is concerned with the identification of biological materials through the
use of various tests.
Solvents - liquids, usually petroleum based, that can
dissolve solids and keep them in solution. May contribute to pollution through
Spatter - dispersion of small blood droplets due to the forceful
projection of blood.
Standard - a statement that describes an acceptable level
of performance, excellence, or attainment in that particular activity.
- A disposition of fragments of powder into the skin as the result of a gunshot
wound of relatively close range.
Subarachnoid hemorrhage - bleeding in the area
between the brain and the thin tissues that cover the brain.
Subdural hematoma -
A collection of blood on the surface of the brain.
Submission - any single
delivery of evidence in a specific investigation.
Submitting Agency - any agency
that submits evidence for examination to any ADFS office. Also referred to as
the “Contributing Agency, Contributor, or Customer”.
Supervised Casework -
analysis performed by a member under the supervision of a certified analyst.
This is generally performed as part of training or as part of an assessment of
an experienced analyst.
Technical Casework Review - the detailed technical
review of bench notes, data, observations and analytical results that form the
basis for the scientific conclusion(s).
Technical Operations Manual - protocols
developed for analyses, examination, comparison, or identification that
prescribes the Good Analytical Practice in a discipline.
Technical Operations -
laboratory activities specific to a discipline directly related to the analysis
or examination of evidence for the purpose of providing information in a
laboratory report, whether verbal or written.
Testable - to be proven true or
Testability - a critical evaluation process that supports or refutes a
Testimony Review - the observation, evaluation, and feedback from
the sworn testimony given by a staff member as part of his/her normal job
duties. Also may be a reviewed by an officer of the court.
Traceability - the
property of a result of a measurement whereby it can be related to appropriate
standards, generally international or national standards, through an unbroken
chain of comparisons.
Theorem - an idea accepted or proposed as demonstrable
truth; often as part of a general theory.
Theory - most logical explanation of
an event that occurs in nature.
Tissue - a part of an organism consisting of an
aggregate of cells having a similar structure and function.
Tomography - the
technique of obtaining an X-ray picture of a selected layer in an object.
Toxicology (forensic science discipline) - analysis of biological samples for
the presence of drugs and other potentially toxic materials.
Trace Evidence -
any analytical procedure utilizing either chemical or instrumental techniques
not specifically covered in other forensic disciplines.
Training Program - a
written description of activities to be performed by a trainee status member of
the Forensic Laboratory for the purpose of enhancing job-related knowledge,
skills or abilities.
Trauma - a physical injury or wound caused by an external
force of violence, which may cause death or permanent disability. Trauma is also
used to describe severe emotional or psychological shock or distress.
Time - the total time a Service Request is in the laboratory, from its receipt
at Evidence Intake until a formal report is issued
Universal Precautions - an
approach to infection control. According to the concept of Universal
Precautions, all human blood and certain human body fluids are treated as if
known to be infectious for blood borne pathogens.
Validation - is the process of
performing a set of experiments that establish the efficacy and reliability of a
technique or procedure or modification thereof. Validation includes
specification of the requirements, determination of the characteristics of the
methods, a check that the requirements can be fulfilled by using the method and
a statement on the validity.
Verification - To confirm the truth or correctness
of something. Vitreous humor - The ocular fluid (from within the eye) that is
often used as a sample for testing in postmortem toxicology.