Forensics Chapter 1 and 2 Test

Forensic Science

Application of science to matters of the law

Observation

Use of one or more of the senses to learn something about the surroundings, a person, or an object

Observations and the Brain

We constantly collect information but our brains apply a filter to that information. Sometimes we have sensory overloads, fill in gaps we have in information, and apply previous knowledge to new situations

Eyewitness Accounts

Reports from individuals often vary and depend on levels of stress, concentration, beliefs, etc.

Innocence Project

Created by Barry C Scheck and Peter J Neufeld in 1992. The project re-examines post-conviction cases using DNA evidence. False eyewitness testimony contributed up to 87% of the convictions in over 200 cases they studied.

Memory Efficiency

An eyewitnesses memory of an event depends on level of interest, stress, concentration, distractions, prejudices, beliefs, motives, and lapse in time since the event.

Role of Forensic Scientist

To find, identify, document, and interpret evidence

Documentation

A forensic scientist must document everything because memory is faulty

Serology

Study of body fluids (blood, etc.)

Toxicology

Study of poisons and their effects (drugs, etc.)

Chemistry

Study of composition of properties of substances (analysis of drugs, arson, explosives, etc.)

Questioned Documents

Study of documents (ink, paper, handwriting, watermarks, etc.)

Fingerprint Analysis

Study of fingerprints (classification, individualization, visualization, preservation, etc.)

Firearm Analysis

Study of firearms and related evidence (bullets, etc.)

Trace Evidence Analysis

Study of trace evidence (hairs, fibers, soil, paint, glass, pollen, dust, etc.)

Tool Marks Analysis

Study of tool marks (impressions made by objects that come into contact with other objects)

Forensic Odontology

Study of teeth

Forensic Entomology

Study of insects

7s's

Secure the scene, separate/interview the witnesses, scan the scene, see the scene, sketch the scene, search for evidence, secure and collect evidence

Securing the Scene

Responsibility of first responder. Must provide medical attention to injured persons. Post tapes, ropes, and barricades around perimeter of scene to exclude people who are not directly involved in the investigation.

Separating/Interviewing Witnesses

Asking witnesses standard questions to help investigators reconstruct the crime and corroborate information about the crime.

Scanning the Scene

Determines where photos should be taken and may identify primary and secondary scenes.

Seeing the Scene

Starting with close up shots of significant aspects of the scene and then moving to photographing key pieces of evidence and finally the entire scene using a wide angle lens.

Sketching the Scene

Initial sketch of the scene first which is not neat but should be as detailed as possible.

Searching for Evidence

Find the perpetrators path of entry/exit and locate pieces of evidence. The specific search patterns can vary but no area should be left unsearched.

Securing and Collecting Evidence

Evidence must be properly packaged, sealed, and labeled but not all evidence is packaged in the same way.

Crime Scene Personel

Police officers, district attorney, crime scene investigators, medical examiners, detectives, and any specialist necessary.

Rough Sketches

Sketch should include fixed points for scale, labels on every item, accurate dimensions of objects, case information (date, time, location, case #, and sketcher's name), and compass direction north.

Smooth Sketches

Should omit lines, labels, and numbers but should include numbers denoting objects/evidence, legend identifying numbered items, scale, compass direction north, and case information.

Two Dimensional Sketches

Incorporates walls and ceiling by creating a map of the 3D space.

Search Patterns

Line, spiral, and grid for large areas or outside. Quadrants or spiral used for small areas such as rooms

Locard's Exchange Principle

Fundamental concept of forensic science created by Dr. Edmond Locard in 1910. States that "when a person comes into contact with an object or other person a cross-transfer of physical evidence or trace evidence can occur.

Trace Evidence

Hair, soil, blood droplets, paint chips, etc.

Physical Evidence

Fingerprints, shoe prints, tire impressions, tool marks, etc. All of these excluding fingerprints reduce the number of suspects

Biological Evidence

Body fluids, hair, plant parts, etc. All of these may make the group of suspects vary small or reduce it to a likely suspect.

Direct Evidence

First hand observations such as eyewitness accounts or police video.

Circumstantial Evidence

Indirect evidence that can be used to imply a fact but not directly prove it. Further broken down into physical and biological.

Chain of Custody

Process that incorporates documentation of who, when, or where of a piece of evidence from it's collection to it's final disposition. Disruption of this documentation could result in the evidence's inadmissibility during court.

Proper Packaging

All evidence is packaged differently.