Fiber Evidence

These flashcards cover essential concepts related to fiber evidence in forensic science, including types of fibers, methods of collection, and their significance in investigations.

What are fibers considered in forensic science?

Fibers are considered class evidence due to their mass production, making it difficult to trace back to a specific source.

What is direct transfer in fiber evidence?

Direct transfer refers to fibers being transferred directly from victim to suspect or vice versa.

What is secondary transfer in fiber evidence?

Secondary transfer occurs when individual fibers picked up from the environment are transferred to another person during contact.

Why is early collection of fiber evidence critical?

95% of fiber evidence falls off or is lost from a crime scene within 24 hours.

What should forensic scientists determine when using fiber evidence?

Forensic scientists look for the type of fiber, its color, the number of fibers found, where they were found, and the origin of the fiber.

What is the first step in the collection of fibers?

The first step is to perform a visual search.

What technique is used for examining fiber characteristics under a microscope?

A microscope is used to identify color, texture, diameter, shape pattern, and cross-section appearance.

Name a common type of regenerated fiber.

Rayon is a common example of regenerated fiber.

What are synthetic fibers made from?

Synthetic fibers are made from polymers which are long strings of repeating chemical units.

How do synthetic fibers differ from natural fibers?

Synthetic fibers are stronger, not damaged by microorganisms, can deteriorate in sunlight, and have very regular diameters.

What is a common property of all animal fibers?

All animal fibers are made of proteins.

What is the main drawback of cotton fibers as forensic evidence?

Cotton fibers are too common and provide little forensic evidence unless dyed.

What type of tests can be damaging to limited fiber samples found at a crime scene?

Destructive tests such as burning or using solvents can damage limited fiber samples.

What is the purpose of using polarizing light microscopy in fiber analysis?

Polarizing light microscopy allows scientists to examine the optical properties of a fiber.

What is the significance of fiber color in forensic matching?

Fiber color is the first step in matching fiber to location.

Name a type of mineral fiber.

Asbestos is a type of mineral fiber.

What is the structure of a textile?

A textile is formed by weaving yarns made from fibers.

What does thread count refer to?

Thread count is the number of threads packed together per given amount of fabric.