Forensic Science s3

These flashcards cover key concepts from forensic science, including various types of evidence, methods of analysis, and tools used in the field.

Impression Evidence

Includes common sources such as shoeprints, tire tracks, tool marks, bite marks, and fabric impressions.

2D and 3D Impressions

2D: Flat impressions (e.g., blood prints on paper); 3D: Depth impressions (e.g., footprints in mud).

Restoration of Serial Numbers

Achieved through chemical etching, magnetic particle inspection, or heat treatment depending on the material.

Casting Materials

Dental stone or plaster is used for soil/mud, while silicone or rubber-based compounds are used for harder surfaces.

Positive Impressions

Raised or deposited material, such as a blood shoeprint.

Negative Impressions

Indented or removed material, such as a footprint in sand.

Rifling

Spiral grooves inside a gun barrel that impart spin to the bullet for accuracy.

Stria

Fine lines or scratches on bullets or tools that help match them to a specific weapon or tool.

Firearm/Toolmark Analysis

Involves microscopic comparison of marks on bullets and casings to determine if they were fired from the same weapon.

Latent Prints

Invisible fingerprints revealed by powders or chemicals.

Patent Prints

Visible prints, such as those made by blood or ink.

Plastic Prints

Impressions left in soft material like wax or clay.

Fingerprint Individualization

Analyzed by ridge patterns, minutiae points, and unique features like bifurcations and ridge endings.

Handwriting Disguise

Altering slant, pressure, or letter formation to conceal handwriting.

Request Exemplar

A handwriting sample taken under supervision.

Non-Request Exemplar

Existing handwriting samples such as letters or notes.

Erasures

Material removed with a rubber or blade, detectable by fiber disturbance.

Obliterations

Covered writing detectable with infrared or UV light.

Charred Documents

Burned documents that may be enhanced using infrared imaging.

Indented Writing

Impressions on underlying pages revealed with ESDA.

Electrostatic Detection Apparatus (ESDA)

Reveals indented writing by detecting pressure marks.

Alternating Light Source (ALS)

Enhances visibility of inks, bodily fluids, and alterations.