Forensic Final Exam Flashcards
What are the three timeframes of trauma?
Antemortem: evidence of healing; Perimortem: no or little healing but bone exhibits a “green” response; Postmortem: dry rough fracture margins often showing different coloration.
Name three types of trauma
Blunt force trauma, sharp force trauma, projectile trauma
Describe blunt force trauma
Depression fractures with sharp or defined edges, radiating fractures fall on flat surfaces.
Describe sharp force trauma
cut wounds (longer on surface than it is deep), stab wounds (deeper than it is long), defense wounds (typically found on the hands or arms).
Describe beveling for gunshot entrance/exit wounds
Entrance wounds will exhibit internal beveling and exit wounds will exhibit external beveling
Describe some different loading forces bones may experience
Compression forces (normal for long bones); shear forces (from crushing blows), torsion forces (resulting in spiral fractures), tension and compression together result in butterfly fractures
Sometimes bullets do not actually cause wounds
Rather the shockwave of air displacement does
Describe the donated body program of the FAC
3 donations per year from 1981-84; 36 per year from 1998-2001; 127 donations in 2009; total of 1,200 individuals in the collection
What information is collected on individuals in the donated body program at the FAC?
name, DOB, place of birth, date and COD, sex, ancestry, stature, weight, photographs, hair and eye color, handedness, number of children, blood type, lifelong occupation, medical histories, any tattoos.
What research is conducted at the FAC?
general decomposition changes in buried vs. embalmed bodies, decomposition on bullets and bullet types.
Describe Freedman’s Ranch
This Texas State Facility houses about 5 acres
How large is the FAC?
About 2.3 acres
How is time since death determined
Forensic entomology, soil analysis, tissue/fluid analysis, experience, number of leaf falls, body appearance, carnivore activity
What are some factors that affect decomposition?
Exposure (inside vs. outside), trauma, blood, clothing (slows decomposition by limiting insect access), surface vs. buried, temperature, scavenger presence
What are some environmental factors that affect decomposition?
Temperature, humidity, sunlight vs. shade, covering, insect access.
What are the stages of decomposition?
Fresh (autolysis), bloat (putrefaction), decay (putrefaction and carnivores), dry (diagenesis).
What changes occur throughout the stages of decomposition?
Early: initial soft tissue changes; Mid: initial skeletonization; Late: bone weathering
Describe 3 blade configurations, 3 blade actions, 2 grip types, and 3 target types from Levi’s lecture
blade: standard smooth, serrated, combination; actions: stab, thrust, slash; grip: forward/extended or reverse/ice-pick; targets: systemic, structural, peripheral.
Describe two types of pathology
Congenital and acquired
What are some categories of acquired pathologies
Degenerative processes, dental disease, infectious and inflammatory, metabolic, traumatic, tumors.
Name some congenital defects:
Cleft palate, dislocations, polydacyly, bifid ribs, spina bifida, spondylosis, dwarfism, scoliosis, cranial suture problems (brachiocephaly, scaphocephaly, anacephaly, craiostenosis).
Degenerative disorders may result in
the fusion of the vertebrae, fusion of the ribs to the sternum, hip fusion.
Name some forms of dental disease
caries, dental wear/attrition, tooth loss, tooth abnormalities, supernumerary teeth
name two nutritional diseases
scurvy, rickets
Describe osteoarthritis
Probably the most common pathological condition and usually involves the destruction of the hyaline cartilage at joint surfaces and imbalances in mechanical stress which result in pitting, erosion, lipping, and eburnation.
What is the context in a forensic field site?
Establishing the relationship of human remains to the physical evidence
What are some discovery methods used in forensic field sites?
systematic pattern search, grid, linear, or spiral searches burial probing and cadaver dogs. Metal detectors, ground penetrating radar, soil resistivity/gradiometer, aerial/infrared photography, LIDAR, gas detectors.
In surface scatter documentation a ___ is essential
datum
What are some criteria used for positive identification?
visual, fingerprint, DNA (mt or nuclear DNA), dental radiographs/charts, skeletal radiographs (dental patterns, frontal sinus patterns, past fractures, etc.),
What rule requires that scientific standards are applied to forensic data presented in a legal context?
Federal Rule 702: the Daubert Rule from Daubert v. Merrell-Dow Pharmaceuticals
The first national online repository for missing persons and unidentified dead cases is
NamUS (National Missing and Unidentified Persons System); started in 2007
NamUS is
the first national online repository for missing persons and unidentified dead cases is
CODIS is
The Combined DNA Index System
NCMEC is
National Center for Missing and Exploited Children
NCIC is
National Crime Information Center
The FBI chose ___ as the standard to be used in CODIS
13 genetic loci
Traits: sexing based on the skull
Walker: supraorbital margin, supraorbital ridge/glabella, mastoid process, mental eminence, and nuchal crest
Traits: sexing based on the pelvis
Phenice: greater sciatic notch, pubic width, ischiopubic ramus, ventral arc, preauricular sulcus, raised auricular surface, subpubic concavity
Traits: sexing based on long bones
Jantz and Spradley
Traits: age estimation for the 1) pubic symphysis, 2) auricular surface, and 3) sternal rib ends
1) Todd and Suchey Brooks
2) Lovejoy
3) Iscan and Loth
Traits: ancestry
Hefner and Ousley
Traits: stature
Fully (anatomical); Trotter and Gleser (regression analysis)
Posterior probability
Probability of belonging to group, assuming it belongs to one of them.
F-typicality
Probability of falling within range of variation, considering sampling variation.
Chi-typicality
Probability of falling within range, ignoring sample variation.
R-typicality
Explicit rank of skull in each sample.
Mahalanobis Distance
Measure of similarity of unknown for each group.
