forensic science

Forensic Science

the applications to matters of science to law

-As well as. . .

The business of providing timely, accurate, and thorough information to all levels of decisions makers in our criminal justice system.

Criminalistics

the scientific examination of physical evidence for legal purposes This term is synomous with forensic science

Criminology

includes the physcological angle, studying the crime scene for motive, traits, and behavior that will help to interpret the evidence

Divisions of Crime Lab

**Physical Science Unit

-chemistry

-physics

**Geology

**Biology Unit(DNA)

**Firearms Unit(tool mark)

**Document Examination Unit

**Photography Unit

Edmond Locard

**French professor

**Considered the father of: criminalistics( understood the importance of nature in crime scenes and other cases.)

**Built the world's first forensic laboratory in France in 1910

Exchange Principle

Whenever two objects come into contact with each other, traces of each are exchanged.

Alphonse Bertillon

Father of: criminal identification

Francis Galton

First to develop a method of: first to develop a method using fringerprints as a means of identification.4f

Dr. Karl Landsteiner

An Austrian physician that identified the A, B, AB, and O blood groups in 1901.

Rudolf Virchow

A German pathologist who standardized a way to preform autopsies one of two ways still used today.

** His cell theory, ("Omnis cellula e cellula") said that cells arise only from other cells.

scientific method

1. Observe a problem

2. Consider a hypothesis or possible solution.

3. Examine, test, and then analyze the evidence.

4. Determine the significance of the evidence.

5. Formulate a theory based on evaluation of the significance of the evidence

Recongnition

ability to distinguish important evidence from unrelated material(which doesn't belong)

Preservation

collection of evidence(properly clothed for the contamtination of other evidence)

Identification

use of scientific testing

Interpretation

gives meaning to all the information(meaning of the labs)(in the court)

Reconstruction

the case events( can be able to put the evidence in chronological order to present the evidence to a jury)(in the court)

direct evidence

eyewitness statements, confessions( not always the best because of biased)

Circumstantial

requires a indriect judegment or inference about what happened

***this type of evidence is not absolute proof, but does provide a general idea of what happened. It may be more reliable than direct.

Testimonial

also known as direct evidence or Prima Facie evidence( a statement made underoath that may be given)

Physical

any object or material that is relevant in a crime

Transient Evidence

temporary; easily changed or lost; usually observed by the first officer at the scene

Pattern Evidence

produced by direct contact between a person and an object or between two objects; most are in the form of imprints, indentations, striations, markings fractures or deposits.

-skid marks

Conditional Evidence

produced by a specific event or action; important in crime scene reconstruction and in determining the set of circumstances within a particular event

**head light

Transfer of Evidence

produced by contact between person(s) or object(s), or between person(s) and object(s)

Associative Evidence-

items that may associated a victim or suspect with a scene or each other; ie, personal belongings

class evidence

common group of objects or persons

example: blood type

Individual

can be identified with a particular person or source(can isolate to one and only source) example: blood DNA

Means—

person has the ability to do the crime

Motive

person has a reason to do the crime

Opportunity

person had the ability to be at the crime

Triangulation

uses two points at the crime scene to map each piece of evidence

Coordinate or grid-

divides the crime scene into squares for mapping.

Baseline

set a north/south line and measures each piece of evidence from this line.

Druggist Fold

is used with larger pieces of paper folded around larger items to hold trace evidence in place. These are then placed insider other containers such as paper bags, plastic bags, canisters, packets and envelopes depending on the type and size of the evidence.

chain of custody

A written record of all people who have had possession of an item of evidence.

Sir Edward Henry

He devised a workable classification system for fingerprints

The Bertillon System

developed the first truly organized system of identifying individuals in 1883.

He believed that everyone could be distinguished from one another by key measurements of their body.

These measurements became known as berillonage.

Dactylosocopy

the study of fingerprints

Arch fingerprint

They do NOT have type delta or cores

Plain Whorl

This print has 2 delta's and therefore it is a __________

Double loop whorl

accidental whorl

comparison

Generally, criminal courts will accept 8 to 12 points of similarity.

IAFIS

The Automated Fingerprint Identification System--a computer system for storing and retrieving fingerprints

visible fingerprints

Made by fingers touching a surface after the ridges have been in contact with a colored material such as blood, paint, grease, or ink.

Plastic Prints

Ridge impressions left on a soft material such as putty, wax, soap, or dust.

Latent Prints

are those that are "hidden" and are not visible to the naked eye. These prints consist only of the natural secretions of human skin and require treatment to cause them to become visible.

accidentals

are marks made on the soles of the shoes that would make the print unique

biometrics

*Use of some type of body metrics for the purpose of identification.

--controls entry or access to computers or other structures; identifies persons for security; helps prevent identity theft or controls social services fraud

testability

A critical evaluation process that supports or refutes a hypothesis

types of handguns

-revolvers

-pistols

types of Shoulder guns

-Rifles

-Shot Guns

tool mark

Features imparted on an object by the contact and force exerted from a tool.

-impressed