Intro


 * "Fibers are used in forensic science to create a link between crime and suspect."
 * Example
 * CSIs may find fibers at a crime scene that match a person's jacket who was there when the crime took place. Although this doesn't mean that that person was there, a jacket with the same fibers was. This can narrow down suspects extremely easily.
 * When we wear clothes, there are millions of fibers that fall off of what we are wearing. If we sit on couces, walk on carpet, or hug people, we pick up and leave fibers. The forensic scientist looks at all the different fibers to tell whether a suspects been in contact with certain people and where they've been.
 * "Unlike fingerprints and DNA evidence, biers are not specific to a single person." Think about it, how many sweaters does the GAP produce and sell? A __LOT.__
 * Fibers are a form of trace evidence
 * carpets
 * clothing
 * linens
 * furniture
 * insulation
 * rope
 * Direct Transfer is either victim to suspect or suspect to victim
 * Secondary transfer - "If a victim has fibers on his person that he picked up and then transferred to a suspect." Basically, if you were at home playing with your guinea pig,when all of the sudden someone blind folds you and puts you in the back of their chevy van, then your guinea pig's hairs would be transferred to your kidnapper.
 * "Early collection of fibers in an investigation is critical. Within 24 hours an estimated 95% of all fibers may have fallen from a victim or been lost from a crime scene."
 * CSIs don't pick up the "duh" fibers. If there were lime green fibers on the victim's clothes, and they lived in a house with wall-to-wall lime green carpeting, the CSIs wouldn't pick up those fibers.

How do forensic scientists use fibers?
 * They ask questions
 * __Type of Fiber__ - What is the composition of the fiber? How common or rare? What suspects or victims or part of the crime scene had this type of fiber on them?
 * __Fiber Color__ - Do the fibers from the suspect's clothes match the color found in the victim's house? Is the type of dye the same?
 * __Number of Fibers Found__ - How many fibers were found - one or hundreds? More fibers suggest possible violence or a longer period of contact.
 * __Where the Fiber was Found__ - How close can you place the suspect to the scene of the crime - in the house, or close to a victim's body?
 * __Textile the Fiber Originated From__ - Are these carpet fibers, or upholstery from a car?
 * __Multiple Fiber Transfers__ - Is ther eonly one type of fiber transferred at the crime scene? Or are there fibers from numerous cources from carpets and clothes and bedding? More sources, longer contact, or possible violence.
 * __Type of Crime Committed__ - Was the crime violent, a break-and-enter, a kidnapping? Each type of crime has an expected pattern of contact between suspect, victim, and crime scene that will be reflected in the transfer of fibers.
 * __Time Between Crime and Discovery of Fiber__ - How long ago did the transfer take place - an hour, a day, a week? Unless the fiber location is undisturbed (such as a bagged jacket or locked room), the value of found fiber is greatly reduced with the passage of time because fibers will be expected to fall off, or fibers not related to the crime can be picked up.
 * Sampling and testing
 * fiber evidence is gathered by...
 * Vacuums
 * Sticky Tape
 * Forceps (like tweezers)
 * Tasks
 * Identify the type of fiber and its characteristics (color and shape)
 * Attempts to match it to fibers from a suspect source (car and home)
 * Two tests that won't damae or alter the fiber
 * __Polarizing LIght Microscopy__
 * uses special microscopes that has a special filter in it that allows the scientist to look at the fiber using specific light wavelengths
 * how a fiber appears can tell the scientist the type of fiber
 * __Infrared Spectroscopy__
 * Emits a beam that bounces off the material and returns to the instrument
 * how the beam of light has changed reveals something of the chemical structure of the fiber, making it easy to tell the differece between fibers that look very much alike
 * __Natural Fibers__
 * such as wool or cotton only need to be looked at with a regular microscope