INVESTIGATIONS

SCIENCE OR ART?

3.5 THINGS SOLVE CASES

THEY ARE?

WITNESS

PHYSICAL EVIDENCE

CONFESSIONS

.5INFORMANTS

– CANNOT BE USED TO PROVE

– NOT USUALLY USED IN COURT

SUCCESS OR FAILURE OF CASE

People commit crimes

“THINGS” become physical evidence

What is PHYSICAL EVIDENCE

PHYSICAL EVIDENCE---any object that can establish that a crime has been committed or can provide a link between a crime and its victim or between a crime and its perpetrator

CAN BE MEASURED

TYPES OF PHYSICAL EVIDENCE

Blood, semen, saliva Documents Drugs Explosives Fibers Fingerprints

Firearms, and ammunition Glass Hair Impressions Paint Soil and minerals Tool marks

WHOSE ARE THOSE ANYWAYS??

Individual characteristics---Properties of evidence that can be attributed to a common source with an extremely high degree of certainty.

HISTORY OF IT ALL

Sir Arthur Conan Doyle

A Study In Scarlet

1887

MID 1800’s NYPD set up a Rogue’s Gallery-1857

– Photographs of known offenders– Arranged by criminal specialty and height– Offenders grimaced, puffed their cheeks to change

their appearance

Rogue is slang for thieves, a wandering beggar, someone who wanders away

By 1858 had over 700 photographs

1884 Chicago established the first municipal Criminal Identification Bureau

1865 U.S. Secret Service was created by Congress to combat counterfeiting

Began guarding the president in 1903 after President McKinley was assassinated

1905 CA Bureau of Criminal Identification

First State Police Force in Pennsylvania Prohibition in 1920, Bureau of Internal

Revenue was responsible for enforcement Lodged in the Dept of the Treasury, they were

referred to as “T-men” 1908 the beginnings of the FBI 1932 FBI established a crime lab

1967 National Crime Information Center (NCIC) established by the FBI– Wanted persons– Stolen property

Guns Vehicles License plates

– Cannot do credit cards

“PACKING THE RECORD”

Get as much information as possible

NCIC INFORMATION CLEARING HOUSE

COMPUTERIZED NETWORK LINKED TO PDs TO PROVIDE INFORMATION ON

STOLEN VEHICLES WANTED PERSONS STOLEN GUNS OTHER CRIME

RELATED INFO

Oldest Forensic Lab LAPD---1932 Created by August Vollmer

Chief from Berkeley

LOCARDS EXCHANGE PRINCIPLE

Edmond Locard (1877-1966)

The exchange of materials between two objects that occurs whenever two objects come into contact with one another

TRACE EVIDENCE

PHYSICAL EVIDENCE THAT RESULTS FROM THE TRANSFER OF SMALL QUANTITIES OF MATERIAL

IDENTIFICATION

THREE MAJOR SCIENTIFIC SYSTEMS FOR PERSONAL IDENTIFICATION– DEOXYRIBONUCLEIC ACID (DNA) TYPING

– ANTHROPOMETRY

– DACTYLOGRAPHY

ANTHROPOMETRY

A system of identification of individual by measurement of parts of the body

ANTHROPOMETRY

Developed by Alphonse Bertillon (1853-1914) Father of criminal identification Bertillon system Every human being differs from every other

one in the exact measurements of their body and that the sum of these measurements yields a characteristic formula for each individual

Eleven physical measurements 1883 implemented on an experimental basis Combines full fact with profile pictures Ancestor of the “mug shot”

DACTYLOGRAPHY

Dates back to the First Century Romans Three categories of latent fingerprints

– Plastic prints—fingers touch against a surface such as newly painted surface, adhesive on envelopes and stamps, explosives, thick layer of dust, putty and adhesive tape

LATENT

LATIN WORD FOR

HIDDEN

Unique and Permanent

They develop at 12 weeks development Stresses in the uterus causes friction ridges to

develop Identical twins have same DNA but different

fingerprints---but may have same pattern types

FRICTION RIDGES

TINY RIDGES IN THE SKIN OF A FINGERPRINT ARE KNOWS AS;

FRICTION RIDGES

LOOPS

WHORLS

ARCHES

WHAT TO LOOK FOR

LOOPS 60-65% OF POPULATION

WHORLS 30-35%

ARCHS About 5%

– Contaminated/visible prints—fingers that have been contaminated with a matter touch a clean surface

– Latent/invisible prints—typically invisible to the unassisted eye. Created when the friction ridges deposit oils and body perspiration on a surface

PRINTS ARE MADE OF:

Natural source—Sweat (98% water and 2% oils) Salts and amino acids and vitamins cause the fingerprint to show when sprayed with a chemical

Environmental source—grease, dirt, pollen, etc.

DEVELOPING LATENT PRINTS

Traditional powders Fluorescent powders Chemicals Cyanoacrylate—Superglue fuming Ninhydrin Iodine

CHANGE THEM????

Impossible to obliterate all the ridge characteristics and scars just help to provide new characteristics for identification

LIVE SCAN FOR FINGERPRINTING

OPTICAL SCANNER

IAFIS FBI 1999

INTEGRATED AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM

BRAIN FINGERPRINTING

OTHER TYPES OF IDENTIFICATION

DENTAL EVIDENCE & BITEMARKS– 1775 Paul Revere—was a dentist– John Wilkes Booth

mid 1960’s Armed Forces Used mainly for id of bodies 1970’s used for id of suspects

• HAIR• Area of the body and race• Manner removed• Shampoo residues• Bleached or dyed• Contaminants in the hair—blood, soil semen• If hair has been subject to trauma• Id of drugs ingested

BLOOD– Approx 10 pints of blood– Most common form of evidence– Human blood?– If recovered in liquid state can tell

Venous Fetal menstrual

HUMAN EXCRETIONS AND SECRETIONS– Saliva, urine, semen, perspiration, vaginal

secretions, feces and vomitus

LIPSTICK AND SECRETIONS– Everyone has unique lip prints that do not change

with age

FIREARMS

TOOL MARKS

DOCUMENTS

HANDWRITING AND HANDPRINTING

COMPUTERS

MOLECULAR STUCTUREDNA

DEOXYRIBONUCLEIC ACIDDEOXYRIBONUCLEIC ACID– Organic substance found primarily in the

chromosomes within the nuclei of cells. These molecules carry the body’s genetic information and establish each person as separate and distinct

DNA is three foot long chemical that is tightly wound inside the 46 chromosomes in each cell of the body

HISTORY OF DNA

• FBI first public sector crime laboratory to accept cases for DNA

• December 15, 1988

• Minnesota testing is done at the Bureau of Criminal Apprehension (BCA)

• Testing can take from 2 weeks to 2 months

CODIS 1998

COMBINED DNA INFORMATION SYSTEM

COMPARE AND EXCHANGE DNA PROFILES

WHAT TO DO FIRST????

OFFICER SAFETY

PUBLIC SAFETY

MEDICAL AID TO VICTIMS

DON’T LET EMS BECOME ERT’S

EVIDENCE

REDUCTION

TEAMS!!!!

IS IT A CRIME SCENE???

TREAT ALL CALLS FOR SERVICE AS A CRIME SCENE UNTIL CONCLUDED OTHERWISE

FIRST THING TO DO!!!!

SURVEY

SECURE

HOW TO SECURE THE SCENE

NATURAL BOUNDARIES

VEHICLES

TAPE

INITIAL PERIMETER--BROAD

WIDE LARGE BIG AMPLE SPACIOUS GENEROUS

WITHIN REASON

PERIMETERS

INNER– VERY RESTRICTED

OUTER– MAKE AS BIG AS POSSIBLE

SECURE WINDOWS AND DOORS WAS ANYTHING ALTERED??

ENTRY/EXIT LOG

PART OF SCENE DOCUMENTATION LOG FIRST TIME IN----LAST TIME OUT

EVERYBODY

QUICK SURVEY– NOTE PATHS THROUGH SCENE

START WRITING

MOVE NOTHING

FIELD NOTES

BEST WAY TO DOCUMENT DETAILS OF A CRIME SCENE

SUSPECT/VICTIM

OFFICER TO RIDE WITH ANYONE GOING IN THE AMBULANCE

OBTAIN STATEMENTS OBTAIN EVIDENCE

– CLOTHES

TECHNIQUE TO WORKING SCENE

FACTSWHAT DO YOU SEE

PROBABILITIES– WHAT MIGHT HAVE HAPPENED

SWAG– SILLY WILD _____ GUESSES

4TH AMENDMENT

MAKE SURE YOU ARE OBTAINING EVIDENCE LEGALLY– SEARCH WARRANT– VERBAL CONSENT

DOES EXIGENCY EXIST?

DOCUMENTING THE SCENE

TAKE PHOTOS ASAP

TAKE MORE THAN LESS

VIDEOGRAPHY– BE CAREFUL OF SOUND

ON OR OFF??

SEQUENCE WHEN TAKING PICTURES

OVERALL-----BROAD------STEP BACK

MEDIUM----CLOSER

CLOSE UP

LARGE AREA

OFFICER SHOULD UTILIZE A

SYSTEMATIC

SEARCH

CRIME SCENE SEARCH

CAN’T COLLECT IT IF YOU CAN’T FIND IT

Zone or Grid Method– Area to be searched is divided– Each person is assigned a part

SPIRAL OR CIRCULAR

Can be used for indoor scenes

Single searcher

LANE

MARK EVIDENCE

SKETCHING THE CRIME SCENE

Why sketch?– Scene will not be distorted– Can be as simple or complicated as needed– Sketch can show direction– Sketch will show more than the view from one

direction– Sketch can be used in conjunction with photos

RULES OF MEASURMENT

All measurements should be made from permanent objects

Verify all measurements—two officers check Always show north When measuring bodies get one measurement

at the head and one at the foot

CARDINAL RULE OF SKETCHING

DECIDE WHAT IS TO BE SKETCHED BEFORE TAKING MEASUREMENTS AND DRAWING OBJECTS

CROSS PROJECTION---MOST COMMON

EXPLODED, BIRDS EYE, OVERHEAD VIEW

Walls are folded down

Shows evidence on walls, such as blood spatter and bullet holes

TRIANGULATION

Straight line measurements taken from 2 fixed points

MOST COMMON IN OUTDOOR SCENES

COORDINATE

Right angles inside

Uses two walls as fixed points

REVIEW

CROSS PROJECTION

TRAINGULATION

COORDINATE

BE SURE TO ADD:

NOT TO SCALE

DUSTING

NOT THIS KIND

HOW TO OBTAIN PRINTS

SEACH SURFACE WITH A FLASHLIGHT– LOOK AT AN ANGLE– IF YOU SEE SOME---PHOTOGRAPH THEM

USE CORRECT BRUSH AND POWDER POWDER COLOR TO CONTRAST WITH SURFACE

NO NEED TO USE A LOT OF POWDER– VERY, VERY MESSY

APPLY LIFTING TAPE

COLLECT A LATENT PRINT

PHOTOGRAPH

DEVELOP

TAPE LIFT

CHAIN OF EVIDENCE/CUSTODY

Maintain scene security throughout process Document collections by recording its location,

date of collection and who collected it Chronological history of evidence Establish chain of custody

PACKAGING

NO BIOLOGICAL STUFF IN PLASTIC

PAPER ONLY

DRY BEFORE PACKAGING

SEAL TO PROVE INTEGRITY

PACKAGE TO PRESERVE AND FOR SAFETY

BIOHAZARDS---MARK

EXAMPLES OF:– BLOOD– SEMEN– TISSUE– BODILY FLUIDS– SHARPS

TRANSIENT EVIDENCE

EVIDENCE THAT WILL LOSE ITS VALUE IF NOT PRESERVED OR PROTECTED SUCH AS BLOOD.

LUMINAL

LIGHT PRODUCING CHEMICAL REATION AND THE HEMOGLOBIN IN BLOOD

CSI MIAMI LUMINAL AND BLOOD

Avoid excessive handling of evidence before and after collection

Transport and submit evidence for secure storage

WHAT NOT TO DO

NO SMOKING NO EATING NO USING THE BATHROOM DON’T TALK TO MEDIA NO TRASH

Take your trash out

Can reveal police actions

BEFORE YOU RELEASE A SCENE---- TALK ABOUT IT

MAKE SURE YOU ARE DONE

CARDINAL RULES FOR CRIME SCENE SEARCH

PROTECT THE CRIME SCENE OBTAIN EVIDENCE LEGALLY CONDUCT THE CRIME SCENE PROPERLY PRESERVE AND MAINTAIN CHAIN OF

CUSTODY

LEGAL JURISDICTION

Establishing the exact location where a crime occurred

Essential to establish jurisdiction of the crime

3 THINGS THAT SOLVE CASES

PHYSICAL EVIDENCE

WITNESSES

CONFESSIONS

INFORMANTS?????

INFORMANTS CANNOT BE USED TO PROVE AND MAY NOT GO INTO COURT

FINALLY……………

Criminal investigation is always in the process of evolving due to scientific, legal and social developments as well as changes in the behavior of criminals.