HOSA: Forensic Science Study Guide

Forensic History and Careers

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Mathieu Orfila

(1787-1853) Founder of forensic toxicology, studied poisons and worked on the Marie Lafarge poisoning case

Sir Francis Galton

(1822-1911) Developed the first classification system for fingerprints, published the book Fingerprints in 1892 and described the loop, arch and whorl of fingerprint patterns

Hans Gross

(1847-1915) A generalist who believed in diverse approaches to forensic science and published the first forensic science textbook, Criminal Investigations, in 1893.

Victor Balthazard

(1852-1950) Paris Medical Examiner who advanced fingerprint, firearm, and hair analysis, showed that fingerprints are unique to the 10^60 and used photography to help identify bullets

Alphonse Bertillon

(1853-1914) Developed anthropometry and was the first to solve a case using fingerprints

Edmond Locard

(1877-1966) Established a forensic lab in Lyons France in 1910, founded the Locard Exchange Principle and focused on trace evidence

Calvin Goddard

(1891-1955) Established the study of firearms evidence in the US, established a variety of police labs in the US and invented the comparison scope.

Anthropometry

System of identification of suspects involving 11 body measurements + descriptions + photos

Criminalistics

Describes forensic analysis of physical evidence

Locard Exchange Principle

Every contact leaves a trace

Juan Vucetich

(1891) Began the first fingerprint files

The Henry Classification System

Classification for fingerprinting in all European Countries

1 in 64 billion

Sir Francis Galton's odds for two fingerprints being the same

The Scientific Method

System in which forensic scientist work

The adversarial system

System in which lawyers work

finder of fact

Judge or jury who determines "right" in a case

Civil Cases

Occur between individuals and must show a preponderance of evidence (51%)

Criminal Cases

Occur when laws have been broken, the government in the prosecutor and and guilt but be shown beyond a reasonable doubt (99%)

Felony

In a serious criminal case, the possibility of greater than 1 year in prison.

Misdemeanor

A minor criminal case, possibility of a fine or less than 1 year in prison.

vior dire

Qualifications of a scientist given in a court of law

subpoena

A statement requiring someone to appear in court and stating when and where the trial will be held.

Gilbert Thomas

(1882) Who used fingerprints officially in the US for the first time

Dr. Henry Faulds

(1880) First to come up with a classification system based on fingerprints

1892

When the first criminal fingerprint identification was made

1901

When the idea of fingerprinting was introduced to England/Wales

Karl Landsteiner

Discovered that blood can be grouped into different types, A, B, AB and O, and received the Nobel Prize in medicine for this work in 1930.

Alec Jeffreys

Geneticist who developed DNA testing

Colin Pitchfork

The first criminal convicted by DNA evidence

Forensic Nurse

Trained to treat trauma patients (assaulted), take blood and tissue samples, collect evidence, photograph and measure wounds.

William Hershel (1856)

The first to use fingerprinting as a method of identification

Crime Scene and Death Investigation

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primary crime scene

The original location of a crime or accident

Secondary Crime Scene

subsequent crime scenes

macroscopic crime scene

the broad crime scene

Microscopic crime scene

the smaller crime scenes in the broad crime scene

Types of information that can be obtained from forensics testing and examination of physical evidence

linkage of persons, scenes, or objects; investigative leads; information on the corpus delicti; information on the modus operandi; proving or disproving witness statements; identification of the suspect(s); identification of unknown substances; reconstruction of a crime

corpus delicti

A crime must be proved to have occured before a person can be convicted

modus operandi

Someone's habits of working; mode of operation.

Crime Scene Management

1. information management

2. manpower management

3. technology management

4. logistics management

First responding officers

the only people to view the crime scene in its most original and pristine condition (ex. police officers, fire department, emergency personnel)

crime scene security measures

When the first responders protect the crime scene

Walk-through

preliminary crime scene survey performed to orient the crime scene investigator to the scene and the physical evidence at the scene

Crime Scene Map

use of imaging technology and mapping technology to create a virtual layout

The W's

who, what, where, when, and why.

Videography

Video recording of the crime scene

Crime scene sketch

Documenting the crime scene in sketches

Geometric Patterns

1. link

2 line or strip

3. grid

4. zone

5. wheel or ray

6. spiral methods

Types of sketches

Rough and finished sketch

Techniques used to obtain measurements for the crime scene sketch

Triangulation; baseline; and polar coordinates

Crime Scene Reconstruction

Process of determining or eliminating the events that could have occured at the crime scene

process in reconstructing a crime scene

1. data collection

2. conjecture

3. hypothesis formulation

4. testing

5. theory formulation

major tasks of documentation

1. note taking

2. videography

3. photography

4. sketching

Coroner

an official who investigates violent, sudden, or suspicious deaths.

Medical Examiner

a medically qualified public officer whose duty is to investigate deaths occurring under unusual or suspicious circumstances, to perform post mortems, and to initiate inquests.

Forensic Pathologist

Physicians specializing in the diagnosis of disease

Cause of death

disease or injury that initiated the lethal chain of events that led to the death

mechanism of death

disease or injury that initiated the lethal chain of events that led to the death

Manner of death

defined as the fashion in which the cause of death came to be

NASH

four manners of death; natural, accidental, homicidal, suicidal

rigor mortis

stiffing in muscles following death

livor mortis

discoloration of the body that occurs from settling of red blood cells. lividity becomes fixed(pressure will not blanch lividity) after about 12 hours. disappears about 36 hours after death

Algor mortis

calling of the body that occurs after death, assuming the ambient body temperature is lower than body temperature

sudden death

A death that occurs within a few hours of the onset of symptoms or death without any systems

incised wounds

caused by a clean, sharp-edged object such as a knife, razor, or glass splinter

autopsy

the examination of a corpse to determine the cause of death

Necropsy

examination of a body after death

Inframammary incision

made in the fold where the lower part of the breast meets the chest wall

types of mechanical trauma

sharp force and blunt force trauma

sharp force

caused by sharp implements

blunt force

Cause by firearms

lead snowstorm

white fragments of lead around the missing tissue

Penetrating gunshot wound

an entrance wound and no exit wound

Perforating gunshot wound

an entrance and exit wound

distance determination

distance from the shooter to the victim

contact/near-contact wounds

result of close range gunfight, suicide, or execution

Carboxy Myoglobin

a compound formed from myoglobin on exposure to carbon monoxide

stippling

the creation of a pattern simulating varying degrees of solidity or shading by using small dots

distant

any distance beyond that which produces stippling

abraded

scraped skin

laceration

cause by gunshot exit wounds

hollow-point bullets

handgun bullets that are designed to enlarge their diameter during a passage through tissue are common

Asphyxia

the interruption of oxygenation of the brain

Carbon Monoxide

a colorless, odorless, and tasteless gas that is slightly less dense than air; toxic to hemoglobin animals