FRSC 300 2nd Exam

William Herschel

Collected the first fingerprints in India

Henry Faulds

Published a paper on his views of fingerprinting, had the idea that the skin ridge is important for identification

Francis Galton

Published the book Fingerprints

Edward Richard Henry

Developed Henry’s fingerprint classification in 1897

Ridge Characteristics/Minutiae

Helps determine the individuality of the fingerprint

Layers of Skin

Epidermis, Dermis, Dermal papillae

Dermal Papillae

Determines the ridges on the surface of the skin

Ridge Patterns

Loops (most common), arches (least common), whorls

OSAC-FRS

Organization of Scientific Area Committees - Friction Ridge Subcommittee

Whorl

Loop

Arch

Types of Fingerprints

Patent (visible), plastic (soft material), latent (invisible)

How to lift prints

Powder dusting, iodine fuming, ninhydrin, physical developer, superglue fuming

Subcategories of Ballistics

Interior, exterior, terminal

Components of a cartridge

Bullet/projectile, propellant, cartridge case, primer

NIBIN

National Integrated Ballistic Information Network

Glass Classification

Soda lime glass, borosilicate/pyrex, tempered glass, laminated glass

GRIM3

Glass refractive measurement 3 system, automated technology to measure the refractive index of glass

3R Rule

Radial crack, right angle, reverse side

Radial Crack

Force of impact is on one side, the 90 degree angle is on the other

Concentric Crack

Force of impact and the 90 degree angle is on the same side

Layers of Soil

Topsoil, subsoil, bedrock and clay horizon

Examination of Soil

Color comparison, sieves, density gradient tubes, low power microscopy, high power microscopy, energy dispersive x ray spectroscopy

Automobile Paint Composition

Electrocoat primer, primer surfacer, basecoat/colorcoat, clearcoat

Analysis of paint

S-ray spectroscopy, pyrolysis gas chromatography, infrared spectrophotometry

Paint evidence is stored in?

Druggist fold

Hair structure

Roots, shaft, medulla, pigment

Cuticle scale patterns

Coronal/crownlike (small rodents), spinous/petal-like (not human), imbricate/flattened scale (human hair)

Cortex

Pigment granules, cortical fusion, ovoid bodies

Medulla patterns

Continuous (pubic hair), interrupted (animal hair), fragmented (human head hair)

Root Development Stages

Anagen (growing), catagen (transitional), telogen (resting)

Postmortem root band

Helps to determine if hair came from a deceased individual, hair in the telogen phase cannot help

Medullary Index

Diameter of the medulla / diameter of the hair shaft, in humans it is 1/3 or less

Medulla Shape

Uniserial/multiserial ladders (rabbit fur)

How much hair needs to be collected for a representative sample

25

Fiber Types

Natural, manufactured

Natural Fibers

Plant, animal, mineral

Manufactured fibers

Organic, inorganic

Organic fiber

Synthetic or natural polymer

Inorganic Fiber

Glass or metal

Dye Composition of Fibers

Thin layer chromatography and visible light microspectrophotometer

Chemical Composition of Fibers

IR-microspectrophotometer, birefringence value

Classification of fires

Accidental, natural, incendiary

Arson

Willfulness and malicious nature

Indication of arson

Multiple points of origin, evidence of forcible entry, valuables missing, trailers used, accelerants present

Flash Point

Minimum temperature of a liquid that emits enough vapor to form an ignitable mixture with the air

Fire Point

Minimum temperature at which liquid produces enough vapors to sustain combustion

Auto Ignition Temperature

Minimum temperature required to ignite a gas or vapor in the air without a spark or flame being present

How to pack fire evidence

Cans and SOMETIMES jars/vials

Extraction Procedures for Fire Evidence

Headspace, adsorption elution, solvent extraction