Presentation on theme: "FS Fall Final Review. Ch 1 and 2 observations and CSI What factors affect our observations? How does the brain process information? How could you become."— Presentation transcript:
FS Fall Final Review
Ch 1 and 2 observations and CSI What factors affect our observations? How does the brain process information? How could you become a better eyewitness?
Forensic investigators recognize, document, collect, and organize evidence left at the scene of a crime. Factors that affect observational skills such as emotion, perception and recall,time of day, level of interest, number of people…
How does your brain work?
Your brain… Filters (what is important, what you notice, your level of interest, who you are with, where you are….) Fills in gaps (you may think you saw it…) Applies previous knowledge (you sort out issues based on what you know)
Direct vs Indirect
Who does what? Who secures the scene and separates witnesses? Who takes measurements and notes location of evidence Who interviews the witnesses
First Find, then
Why secure the scene?
Identify the regions of hair
What part of the hair is shown?
Human or NON-human Cuticle?
Consistent? Dissimilar? Inconclusive?
Is Hair CLASS or INDIVIDUAL evidence?
Locard Every contact leaves a trace Duration Intensity Materials used
Fingerprints Alphonse BertillionAlphonse Bertillion –Anthropometry-use of body measurements for identification –Francis Galton-suggested 3 categories-Arches, loops and whorls 1999 – US v. Byron C. Mitchell-case that provided 3 principles of fprint1999 – US v. Byron C. Mitchell-case that provided 3 principles of fprint 1. unique 1. unique 2. unchanging 2. unchanging 3. can be used to ID individuals 3. can be used to ID individuals
Kinds of Crime Scene Prints Patent /Visible prints –Patent /Visible prints – –made by fingers touching a surface after ridges have been in contact with a colored materials (blood, paint, etc.) Plastic Prints –Plastic Prints – –ridge impressions left on a soft material (putty, wax, soap or dust) Latent/invisible prints –Latent/invisible prints – –caused by the transfer of perspiration/oils on finger ridges to the surface of an object
Identify each fingerprint pattern. Right Hand Left Hand Right Hand
How can we use these?
What Can be learned from tire impressions? What type of impression is shown?
What can you learn from studying the gait (walking pattern)