Chapter 3 Flashcards
The Various forms of Physical evidence
What is identification?
Has as its purpose the determination of the physical or chemical identity of a substance with as near absolue certainty as existing analytical techniques will permit.
common types of physical evidence
Blood, semen, saliva. documents, drugs, explosives, fibers, fingerprints, firearms & ammunition, glass, hair, impressions (tire markings shoe prints, depressions in soils glove and fabric impressions, bite marks foodstuffs) organs and physiological fluids, paint, petroleum products (gas, arson grease/ oil) plastic bags (garbage bags) plastic, rubber and other polymers, powder residues, serial numbers, soil and minerals. tool marks, vehicle lights, wood and other vegetative matter.
Individual characteristics
Properties of evidence that can be attributed to a common source with an extremely high degree of certainty. ridge characteristics of fingerprints, random markings on bullets, tool marks, irregular and random wear patterns in tire or footwear impressions, handwriting characteristics, irregular edges of broken objects that can be fitted together, sequentially made plastic bags.
Class Characteristics
Properties of evidence that can be associated only with a group and never witha single source.
IAFIS
Integrated Automated fingerprint Identification system
CODIS
Combined DNA index system. Enables federal state and local crime laboratories to electronically exchange and compare DNA profiles, thereby linking crimes to each other and to convicted offenders.
NIBIN
National Integrated Ballistics information network, maintained by the bureau of Alcohol, tabacco, firearms and explosives. allows firearms to analysts to acquire, digitize and compare markings made by a firearm on bullets and cartridge casings from crime scenes.
PDQ
The international forensic automotive paint Data query, data base contains cheical and color information pertaining to original automotive paints.
SICAR
A commercially available computer retieval system for comparing and identifying crime scene shoe prints known as SICAR Shoeprint image capture and retrieval.
Rigor Mortis
A medical condition that occurs after death and results in the stiffening of muscle mass. The rigidity of the body gradually disappears 24 hours after death and disappears within 36 hours
Livor mortis
A medical condition that occurs after death and results in the settling of blood in areas of the body closest to the ground, happens when the heart stops pumping blood, blood will settle in certain areas, good to notice if the body has been moved.
Algor mortis
postmortem changes that cause a body to lose heat, until it reaches the ambient or room temperature.
How is gender determined from bones
an examination of bones may reveal their sex, approximate age, race and skeletal injury.
what is a forensic entomologist?
The study of insects and their relation to a criminal investigation. can be carried out by studying the stae of development of maggots or insect sequence of arrival.
Role of the pathologist
to figure out the time of death, who the victim was, why and how were the injuries produced. Five catagories, natural, homicide, suicide, accident or undermined.
