How observant are you? Honors Forensic Science T. Trimpe 2006

How observant are you?

Honors Forensic ScienceT. Trimpe 2006 http://sciencespot.net/

Which is the correct penny?NO CHEATING! You cannot look at a real penny!

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Chapter 1: Introduction

Modern Advances to Evidence Processing

Modern Scientific Advances

Advancements in computer technology Overall increase in knowledge Increased speed & accuracy of

common procedures Spectrophotometry Chromotography Gel electrophoresis

Extraction and analysis of DNA 1st profiling test done in 1984

Establishment of computerized databases linked via the internet

Crime Laboratories

History 1923 - Oldest contained in

LA Police Dept. 1932 – FBI offered services

to all law enforcement agencies in the country Today – FBI Crime Lab in

Quantico, VA is the world’s largest forensics lab

Performs over 1,000,000 examinations/yr

1981 – FBI’s Forensic Science Research and Training Center opened

History cont.

US has no nationalized system of labs resulting in local jurisdictions operating their own (~350 nationwide) Informal exchange of information between local

jurisdictions often occurs

Extensive growth of the # of labs and services offered in forensics labs Court decisions in the 1960’s greater stress on

securing scientific evidence Increased scientific capabilities of forensics labs Increase in crime rate drug-related arrests require

testing Advent of DNA profiling fast, accurate, ability to

extract from a multitude of sources

International Labs

Great Britain System of National

Facilities (6 for England and Wales)

Fee-for-service Police and law

enforcement agencies charged for tests

Many private labs have popped up profit

Canada Services provided

by 3 government-funded groups

Basic Services of a Crime Lab

Physical Science Unit Applies chemistry, physics, and geology to ID and

compare physical evidence Examines: drugs, glass, paint, soil, etc

Biology Unit DNA profiling

Firearms Unit Examines: firearms, discharged bullets, casings,

ammunition, etc.

Document Examination Unit Studies handwriting, typewriting Looks at ink, imprinting, erasures, etc.

Photography Unit Examines and records physical evidence Uses specialized photographic techniques

Optional Services

Toxicology Unit

Latent Fingerprint Unit

Polygraph Unit

Voiceprint Analysis Unit

Crime-scene Investigation Unit

Forensic Psychiatry

Forensic Odontology

Forensic Engineering

Forensic Computer and Digital Analysis

TPS – aka – Think-Pair-Share

Question: What are some skills/characteristics that a good forensic scientist should possess?

Think – 2 min: write your thoughts in your notes

Pair – 2 min: Discuss your list with your table

Share – Each table shares the 2 most important skills/characteristics

How good are your observation skills?You will have 30 sec to remember as much as possible from the picture that will appear. You will then be asked 5 ?s

Observation Questions

1. What time was it on the clock?

2. How many people were in the scene? How many males? females?

3. Describe the person at the front of the line. Was it a man or a woman? Was he or she wearing a hat? What kind of clothes was the person wearing? Could you tell how tall the person was? Did he or she have any distinguishing features?

4. What day of the month was it?

5. Did you notice anything unusual in the picture?

What makes a good forensic scientist?

Working knowledge of scientific methods and how to apply them to a variety of situations.

Good laboratory techniques

Analytical (focuses on facts and numbers)

Very observant

Ability to think outside of the box

Excellent communication skills

Analysis of Physical Evidence

Of all things admissible in court, physical evidence is free of inherent (unavoidable) error or bias.

Processed via scientific methods Process using strict guidelines to ensure careful, systematic

collection, organization, and analysis of information.

Frye v. United States In order for evidence to be admitted to trial, the procedure/technique/principles must be “generally accepted” by the scientific community. Is this approach still applicable in modern times when new

advances are being made rapidly? (As opposed to 1923 when the ruling was made)

Cont.’d

As decided in Daubert v. Merrell-Dow Pharmaceuticals, Inc.: In lieu of “general acceptance”, an alternative, Rule 702 of

the Federal Rules of Evidence, allows for expert testimony. Must be based on sufficient facts or data Is the product of reliable principles and methods The witness has applied the principles and methods reliably

to the facts of the case

An expert witness is someone determined, by

the court, to possess a particular skill or

knowledge in a trade or profession that is not

expected of the average person.

Proper Recognition, Collection, and

Preservation of Evidence Remember Locard’s Exchange

Principle?

Evidence is virtually WORTHLESS if it has been contaminated, improperly documented, or tampered with!

See Appendix A, p. 674, in your text to see the guide to evidence collection. We will cover some of this

throughout the course.