Intro Forensics Key Terms

behavioral sciences

the scientific discipline that involves the determination of a person's competency

questioned documents

a field that involves the comparison of handwritten or typewritten documents to determine their source or authenticity.

forensic anthropology

deals with identifying people who cannot be identified through soft tissue features, such as fingerprints or photographs, but can be identified through skeletal remains

forensic science

Describes the science of associating people, places, and things involved in criminal activities

forensic odontology

deals with the identification of human remains via intact teeth and bitemark comparisons

chain of custody

the documentation of the location of evidence from the time it is obtained to the time it is presented in court

toxicology

the chemical analysis of body fluids and tissues to determine if a drug or poison is present

forensic pathology

involves the determination of cause and manner of death in cases in which death occurred under suspicious circumstances

forensic engineering

involves failure analysis of materials and constructions, also may involve traffic accident reconstruction

criminalists

captures the various aspects of applying scientific and technological methods to the investigation and resolution of legal matter

American Society for Testing and Materials, International (ASTM)

develops voluntary consensus standards for materials, products, and systems that promote safety, reliability, and quality

American Society of Crime Laboratory Directors (ASCLD)

develop leadership and excellence in which crime laboratories are held to a high standard

ASCLD Lab Accreditation Board

improve standards of crime laboratories to their highest quality

Forensic Science Education Programs Accreditation Commission (FEPAC)

develop and maintain standards that recognize high quality undergrad and post grad programs

Technical Working Group on Education and Training in Forensic Science (TWGED)

develop standardized curriculum criteria for university programs to follow

questioned evidence

original source of the evidence is unknown

negative control

material that is expected to give a negative result with test reagents

direct transfer

evidence that is transferred from a source to a location with no intermediaries

Locard’s Exchange Principle

when two things come into contact, information is exchanged

trier of fact

the person or persons who determine guilt or innocence in a trial

known evidence

original source of the evidence is known

indirect transfer

evidence that is transferred from a source to a location and involves one or more intermediaries

class

group of objects with similar characteristics

positive control

material that is expected to give a positive result with test reagents and serves to show that the test is working properly

probative value

usefulness data has in proving or disproving a hypothesis

christmas tree stain

the traditional method used for sperm identification

brentamine fast blue B

a presumptive test for semen

luminol

reacts in the presence of hemoglobin, when an oxidizer is applied

benzidine

a commonly used catalytic color test that is a presumptive test for blood

phenolphthalein

a commonly used catalytic color test that is a presumptive test for blood

tetramethylbenzidine

a commonly used catalytic color test that is a presumptive test for blood

leucomalachite green

a commonly used catalytic color test that is a presumptive test for blood

prostate specific antigen, p30

developed by Sensabaugh, detection of p30 is a confirmation for semen

fluorescein

a chemical used to check for the presence of blood; prepared in much the same way as luminol

acid phosphatase

a common enzyme in nature that occurs at a very high level in semen

heterozygous

a person inherits different forms of the same gene

homozygous

a person inherits the same form of a gene from the mother and the father

genotype

the genetic description of the allele

PCR

a method for replicating DNA by denaturing double-stranded DNA, adding primers to one end of each strand, and then adding individual nucleotides until a complete complementary strand is built

allele

multiple genes at several locations

CODIS

national database of DNA profiles administered by the FBI

STR

short repeating sequences of DNA

phenotype

the visible manifestation of variability of alleles

denaturation

to separate double-stranded DNA into single strands

gene

a section of DNA that provides for the formation of specific proteins that form all physical and other characteristics in a person (or other organism)

OSHA

Occupational Safety and Health Administration

NIOSH

National Institute for Occupational Safety and Health

CDC

Centers for Disease Control

MSDS

Material Safety Data Sheet

PVC

Polyvinyl Chloride

HBV

Hepatitis B Virus

HCV

Hepatitis C Virus

HAZMAT

Hazardous Materials

HIV

Human Immunodeficiency Virus

PPE

Personal Protective Equipment

barbituates

a group of chemical substances based on the compounds barbituric acid and thiobarbituric acid

drug

a natural or synthetic substance designed to produce a specific set of psychological or physiological effects on the human body, or, in some cases, other animals

crack

a form of crystalline cocaine free base

Uniform Controlled Substances Act

model state law developed to control substances, as well as possession and distribution of the drugs

controlled substances

refers to a substances' inclusion in part of the Federal Code called the Controlled Substances Act

narcotics

drugs that relieve pain and cause sleep

usable quantity

an amount of a drug that is likely to have a demonstrable psychoactive effect on an average person

stimulants

drugs that elevate one's mood. They help people feel better who are sad or depressed. They give people extra energy

excipients

substances that may mimic the activity of the main illicit drug

Pure Food and Drugs Act

legislation passed in 1906 that prohibited interstate commerce in mislabeled or adulterated food or drugs

metabolite

the altered form of a drug or other substance, result of metabolism

pharmacology

the study of the effects of drugs on humans

distribution

the delivery or spreading of drugs throughout the body, accomplished by the bloodstream

addiction

a condition of physical dependence on a drug that is manifested by symptoms of withdrawal if the drug is not taken

withdrawal

a set of symptoms brought on by withholding a drug to which a user has become addicted

synergism

drugs work together to magnify effects or create effects that would not have occurred otherwise

dependence

a psychological need for a drug

drug screen

a test or tests that give presumptive indication that a drug is present in the body

pharmacokinetics

the study of movement of drugs in and out of the body

tolerance

a phenomenon whereby the body's organ systems adapt to a drug

metameric colors

colors that appear to match in one set of lighting conditions, but not in another

staple fiber

natural fibers or cut lengths of filament typically being 7/8–8 inches

spinneret

a shower headlike device with a hole or holes, through which spinning dope is extruded

lumen

the hollow space enclosed by a plant cell wall

delustrants

finely ground particles of material that are introduced into the spinning dope; diffract light and reduce luster

refractive index

a measure of how light bends and changes speed as it passes from one transparent medium to another

filaments

type of fiber having indefinite or extreme length

cross-sectional shape

the shape of an individual filament when cut at a right angle to its long axis

interference colors

colors seen when waves of light interact with each other to produce constructive or destructive waves of light

microfiber

manufactured fibers that are made with diameters of about 6 μm

architectural paints

household paints found in residences and businesses

solvent

chemicals that dissolve the binder and give the paint a suitable consistency for application

binder

portion of the coating, which allows the pigment to be distributed across the surface

pretreatment

the first process in the automotive finishing process; typically zinc electroplating and is applied to the steel body of the vehicle to inhibit rust

product coatings

coverings applied in the process of manufacturing products, including automobiles

Paint Data Query (PDQ)

a project run by the RCMP that stores the data from many databases of paints

ninhydrin

a method used for the visualization of latent prints; develops prints on porous surfaces by reacting with amino acids in the latent print residue

aqueous leucrocrystal violet

a method used for the visualization of latent prints; used to enhance and develop latent prints stained with blood on porous or nonporous surfaces

core

the central portion of the loop

minutiae

friction ridge characteristics

small particle reagent

a method used for the visualization of latent prints; a physical development technique in which small black particles adhere to the fatty substances left in print residues

DFO

a method used for the visualization of latent prints; a ninhydrin analog that reacts with the amino acids present in body proteins

automated fingerprint identification system (AFIS)

computerized databases of digitized fingerprints that are searchable through software

vacuum metal deposition

aphys method used for the visualization of latent prints; a process that evaporates gold or zinc in a vacuum chamber, which coats the specimen surface with a microscopic layer of metal

physcial developer

a method used for the visualization of latent prints; a silver-based liquid reagent that reacts to lipids, fats, oils, and waxes present in the print residue