Forensic Science: Hair, Fiber, Fingerprint, and DNA Analysis

Requires a microscope to see.

Microscopic

Can be seen with the naked eye.

Macroscopic

The protein that composes a strand of hair.

Keratin

Hair Follicle

Hair Follicle

Class Evidence

The classification of evidence when the follicle of the hair is not present.

The top layer of skin.

Epidermis

The Cuticle, The Cortex, and The Medulla.

Hair Shaft Parts

The part of the hair shaft that contains scales that can be seen under a microscope.

Cuticle

Beard, Head, Body, Pubic, Underarm, Eyelash/Eyebrow.

Types of Hairs

Plucking, forceps, adhesives.

Hair Collection Methods

Hair color, texture, ethnicity, or identity if the follicle is present.

Forensic Knowledge from Hair

The famous political leader whose murder was solved due to hair analysis.

Napolean Bonaparte

The smallest unit of a textile.

Fiber

States, 'every contact leaves a trace.' Fallen fibers are picked up during normal activities.

Locard's Principle of Exchange

Vacuuming, Adhesive removal, Plucking.

Fiber Collection Methods

Derived from animals.

Natural Fiber

Produced in a lab.

Synthetic Fiber

Cotton, Wool, Hemp.

Examples of Natural Fibers

Acrylic, Nylon, Rayon, Polyester.

Examples of Synthetic Fibers

Class.

Fiber Evidence Classification

Fiber Burn Analysis.

Fiber Test

Core

The center part of a loop or whorl in fingerprint analysis.

The triangular pattern of a fingerprint.

Delta

Loops, Whorls, Arches.

Fingerprint Patterns

Arches.

Rarest Fingerprint Type

Each person's fingerprints are unique, easy to identify suspect.

Usefulness of Fingerprints

A visible fingerprint.

Patent Fingerprint

Latent Fingerprint

An invisible fingerprint.

A 3D print.

Plastic/Impression Fingerprint

Identifying matches in minutiae patterns.

Fingerprint Matching

Burning, Acid, and Gloves.

Fingerprint Alteration Methods

Glue fuming, Chemical Reactions, Dusting, Alternative Light Sources.

Methods to Make Latent Prints Visible

Deoxyribonucleic Acid.

DNA

Nucleus, mitochondria.

DNA Location

It is individual evidence that can help find suspects and solve crimes.

Importance of DNA in Forensics

Adenine, Thymine, Cytosine, Guanine (AT & CG).

Nitrogenous Bases in DNA

Family relationships, identity.

DNA Profile Information

The Boston Strangler.

Real Life DNA Case

Low Velocity (nose bleed), Medium Velocity (blood slinging from a knife), High Velocity (gun shot).

Blood Spatter Types

Diameter increases as it falls from an increasing height.

Blood Drop Diameter

100 ft/sec.

Fastest Speed of Blood

25 ft/sec.

Fastest Speed of Gravitational Drop

Presumptive blood test.

Blood Test

The typical fire makes a V pattern.

Fire Pattern

Insurance fraud, crime concealment, entertainment, revenge.

Reasons for Arson Crimes

It has to be packaged in glass containers.

Arson Evidence Packaging

The study of firearms.

Ballistics

Long guns and Handguns.

Firearm Classification

IBIS/NIBIN.

Ballistics Database

The striations can be used to match crime scene evidence to firearms used in the crime.

Bullet Evidence

The breechmarks and firing pin patterns can be used to identify weapons used.

Casing Evidence