Forensic Science SFS1. Students will recognize and classify various types of evidence - PowerPoint Presentation

Slide1

Forensic Science

SFS1. Students will recognize and classify various types of evidence in relation to the definition and scope of Forensic Science.

a. Compare and contrast the history of scientific forensic techniques used in collecting and submitting evidence for admissibility in court (e.g.

Locard’s

Exchange Principle, Frye standard,

Daubert

ruling).Slide2

ESSENTIAL QUESTIONS

What is forensic science?What is evidence and how is it used by forensic scientists?What are the characteristics of a typical crime lab?

Which historical forensic scientists laid the ground work for modern forensic science?

What is the importance of

Locard’s

Exchange Principle?Slide3

ESSENTIAL QUESTIONS

What is the basic methodology used by forensic scientists?What are the steps that must be followed in the pursuit of justice?What is the importance of the Federal Rules of Evidence?

What is the importance of the Frye Standard?

What is the importance of the

Daubert

Ruling?Slide4
Slide5

Forensic Science is…

the application of science to those criminal and civil laws that are enforced in a criminal justice system.Criminalistics is…

the examination of physical evidenceSlide6

A forensic scientist…

is a generic term for a professional or academic specialist in a particular field. They are typically referred to as a “forensic toxicologist” or a “forensic pathologist,” etc.

A criminalist…

is the fancy word for a “lab technician” or a “crime scene investigator.”Slide7

Professional and Academic Specialties

CriminalisticsAnthropologyPsychiatry and Behavioral Science

Jurisprudence

Odontology

Engineering Sciences

Pathology/Biology

(incl. medical, entomology, botany)

Questioned Documents

Toxicology

Digital and Multimedia SciencesSlide8

Laboratory Analytical Specializations

Chemistry (incl. toxicology, paint/polymers, instrumentation)Computer Analysis

DNA Analysis

Explosives

Firearms and

Toolmarks

Audio, Video, and Image Analysis

Latent Print

Materials Analysis

(incl. mineralogy, metallurgy, elemental analysis)

Questioned Documents

Racketeering Records Analysis

Trace Evidence

(incl. anthropology, odontology, hairs, fibers)Slide9

What do they do?

A forensic scientist or criminalist’s primary job is to study the different types of evidence found at a crime scene, but s/he must also testify as an expert witness, perform scientific research and

train others

.Slide10

Criminalists use laboratories to help them examine…

EVIDENCE –anything that tends to establish or disprove a fact documentstestimony (oral or written)

exhibits

demonstrative

(models, diagrams, photographs)Slide11

Crime Laboratories

There are nearly 400 crime labs in USFederal, state, county, and municipal (local)Most function as part of a police departmentOthers fall under direction of the prosecutor or district attorney’s office

Some work with labs of the medical examiner or coroner

A few are affiliated with universities or exist as independent agencies in governmentSlide12

There is

NO national system of forensic laboratories, nor is there a mandatory process for accreditation so…there is little organization and consistency among US forensic labsSlide13

Most labs are maintained by states for regional areas

GBI has 7 regional labs; Eastern Regional Lab is located in Augusta and serves 15 countiesSlide14

FBI Crime Lab Services

Biometric Analysis (DNA and latent print analysis)Forensic Response (crime scene documentation, hazardous evidence response, photographic operations)Terrorist Explosive Device Analysis

Scientific Analysis

(counterterrorism and forensic science research, questioned documents, firearms/

toolmarks

, cryptanalysis and racketeering, trace evidence, chemistry)Slide15

GBI Crime Lab Departments

Chemistry (drug and fire debris, expert testimony, law enforcement education) Firearms (firearms and components, bullets and cartridges, distance determination tests,

toolmarks

, serial number restoration, NIBIN database)

Forensic Biology

(serological and DNA analysis for identification and individualization)

Latent Prints

(identification and comparison of fingerprints and AFIS database)

Medical Examiners

(forensic pathology)Slide16

GBI Crime Lab Departments

Operations Support (evidence receiving, entry into LIMS, evidence transport, storage/disposition of evidence)Toxicology (drugs/alcohol/poisons in human biological samples) *

Trace Evidence

(paint, plastic, hair, fiber, glass, fractured materials, general materials, gunshot residue)

Implied Consent

(breath alcohol testing program)

Quality System

(maintaining lab accreditation)Slide17

Crime Lab Statistics

~3.8 million requests for servicesMost were submitted to state labs (58%)38% of these requests were outsourced to other labs (public/private)~75% of all analyses are for controlled substances identification (33%)

, DNA from arrestees/convicts

(24%)

, and toxicology (15%)

~15% of cases are backlogged (>30 days)

most are DNA analysesSlide18

Crime Lab Statistics

Employ over 14k full-time personnelAverage salary for an analyst is ~$55k/yrCombined operating budget of ~$1.7 bil

.

Most labs perform controlled substances ID

(81%)

, latent print analysis

(63%)

, and biological analysis

(62%)

Oldest lab in world is in Lyons, France

(1910)

Oldest lab in US is LAPD

(1923)

Largest lab in world is FBI

(1932) Slide19

Federal Forensics Labs

Federal Bureau of InvestigationTerrorism, counterintelligence, cyber crime, public corruption, civil rights, organized crime, white-collar crime, violent crime, and weapons of mass destruction

HQ in Quantico, VA; 56 field offices

Operated by the Department of Justice (DOJ)Slide20

Federal Forensics Labs

Drug Enforcement AgencyDrug-related crimes

HQ in Arlington, VA; 313 field offices (domestic and foreign)

Operated by the DOJ Slide21

Federal Forensics Labs

Bureau of Alcohol, Tobacco, Firearms,

and Explosives

Crimes involving alcohol, tobacco, firearms, explosives, suspected arson, and organized crime

Forensic Science Labs in Atlanta, CA, and MD; Fire Research Lab in MD; 34 field offices (domestic and foreign)

Operated by the DOJSlide22

Federal Forensics Labs

United States Postal I

nspection

S

ervice

Crimes involving the mail

HQ in Dulles, VA

Operated by the United States Postal Service

United States Fish & Wildlife Service

Crimes against wildlife

HQ in Ashland, OR

Operated by the Department of the InteriorSlide23

Song Ci

(1248)First written account of using medicine and entomology to solve criminal casesPurkyně (1823)First

system of classification

of fingerprints

Bertillon

(1879)

Father of criminal identification

Developed the science of anthropometry—the taking of body measurements as a means of distinguishing people

Gross

(1893)

Father of criminal profiling

First instructive book focusing on human nature and the motives of a criminal

Locard

(1910)

Father of forensic science

Developed the idea of cross-transfer of evidence

Founders of

ForSciSlide24

Locard’s

Exchange Principle“Any action of an individual, and obviously the violent action constituting a crime, cannot occur without leaving a trace.”This simply means that every time you make contact with another person, place, or thing, it results in a cross-transfer of physical materials.Slide25

Criminal Justice and the Law

US Constitution is the supreme body of laws that trumps allStatutory Law (legislation)Enacted by a governmental body or agency having the power to make laws (such as Congress)

Common Law

(case law)

Made by judges

Precedents allow for consistency and predictability in how the law is appliedSlide26

Civil Law (code law)

Collection of codified statutesPrecedents are given less weightDeals with relationships between individualsMore concerned with assigning blame than with establishing intent“Preponderance of evidence” is required to convict

Criminal Justice and the LawSlide27

Criminal Law

(penal law)Body of rules that defines conduct prohibited by the state and assigns punishment for breachPunishments are related to the “guilty act” and the “guilty mind”Distinguishes between “major” and “minor” crimes“Beyond a reasonable doubt” is required to convict

Criminal Justice and the LawSlide28

Types of Crimes

A broken law is called a violation.INFRACTION “regulatory offenses”Least serious class of crimeCan be proceeded against without

the right to a jury trial and/or

indictment

Punishable by fines

Include traffic tickets/violations, jaywalking, littering, disturbing the peaceSlide29

MISDEMEANORMore serious class of crime than infraction

Punishable by 1 year or less in prison, house-arrest, probation, community service…Include DUI, vandalism, petty theft (<$500), prostitution, public intoxication, disorderly conduct, trespassing…Types of CrimesSlide30

FELONYMost serious class of crime

Punishable by more than 1 year in prison or by deathInclude kidnapping, arson, burglary, aggravated assault/battery, robbery, murder, grand theft (>$500), rape…Types of CrimesSlide31

The forensic scientist, or expert witness, has an

obligation to be an advocate for the truth, and should not take sides for either the defense or prosecution.The person who presents scientific evidence must establish credibility via credentials, background, and experience.

Criminal Justice and the LawSlide32

The Frye standard (Frye vs. US, 1923)

Frye was convicted of murder. On appeal, defendant’s counsel offered an expert witness to testify to the result of a deception (pre-polygraph) test, claiming that during the first trial, the testimony was not accepted.SCOTUS let the conviction stand and stated that scientific evidence must have gained “general acceptance” to be accepted in courtAt that time, the deception test was not “generally accepted”…Slide33

The Frye standard

Commonly called the “general acceptance” testDictates that expert opinion based on a scientific technique is admissible at trial only if the methodology or science is “generally accepted” as reliable in the field of studySlide34

Federal Rules of Evidence (1975)

To be acceptable in court, evidence must be RELEVANT; that is, it should be both MATERIAL and PROBATIVE.

Material evidence

is “of consequence to the determination of the action”

Probative evidence

has “the tendency to make a fact more or less probable than it would be without the evidence”Slide35

The Daubert standard

(Daubert vs. Merrell Dow Pharmaceuticals, 1993)Two families sued Dow claiming that childrens’ birth defects had been caused by mothers’ prescription drugsThe trial court decided that the petitioners’ experts’ testimony did not meet the Frye standard

In appeals, SCOTUS decided that the Frye Standard was no longer appropriate because of technological sophistication and deferred to the FRESlide36

The Daubert standard

The Frye standard was superseded by the Rules’ adoptionThe judge is the “gatekeeper” and must evaluate the expert’s scientific knowledge based on the following criteriaTheory or technique can be/has been testedSubject to peer-review and publicationKnown or potential error ratesTechnique standardization

Widespread acceptance within the fieldSlide37

The CSI effect

First reported in 2004 describing the effect of TV programs featuring forensic science on trial jurorsFamilies and jurors seem to expect instant answers from techniques that often take days/weeks/months to process and result in less definite conclusionsSlide38

The CSI effect

Jurors tend to expect more forensic evidence than is available or necessaryComplaint from juror that the prosecution had not dusted the lawn for fingerprintsORJurors have greater confidence in forensic evidence than is warrantedMurderer acquitted despite eyewitness testimonySlide39

Steps in Pursuing Justice

Once a crime is committed and discovered…A suspect may be identifiedPolice investigate what may have happenedInformation is collectedCrime scene is documented and searched for evidence

Info is assembled into a report for the prosecutor

Investigation ensues

If enough evidence can establish

probable cause

, then an arrest warrant is issuedSlide40

After a suspect is in police custody, s/he is…

Informed of his/her Miranda rights (required prior to interrogation) and processed (“booked”)Brought before a judge for arraignment to hear charges and enter a plea

Steps in Pursuing JusticeSlide41

After a defendant’s plea is made…

A preliminary hearing is conducted before a judgeThis is to determine whether there is enough evidence to proceed to a trialProbable cause must be established

Federal gov’t and some states may use a

grand jury

for felony cases

Defendant is not entitled to counsel

Steps in Pursuing JusticeSlide42

Pleading “not guilty by reason of insanity”…

Requires the defendant to prove the inability to “know right from wrong” at the time of the commission of the crimeIt removes the requirement to demonstrate intentSteps in Pursuing JusticeSlide43

A person is presumed innocent until proven guilty

The burden of proof rests with the prosecutionOnly 50% of all arrests lead to convictionOnly 25% of all convictions are sentenced to 1+ years in prisonSteps in Pursuing JusticeSlide44

Plea bargaining can reduce the burden on the court by allowing a defendant to plead guilty to a lesser charge and avoid a trial

90% of all cases are “pleaded down”Steps in Pursuing JusticeSlide45

Methodology

The Scientific Method does not and cannot work for the forensic sciences in its standard form because it does not work for past events, which cannot be observed, predicted or deduced from physical evidence, and cannot be tested experimentally.Slide46

Methodology

Acquire information about the incident of concern from primary witnessesAnticipate questions that others with vested interest in the incident will ask in the futureThis requires experience and imaginationSlide47

Methodology

Examine evidence with a focus on finding answers to the anticipated questionsCompare the consistency of alleged events (hypothesis as proposed by the witness statements) with evidential data, obtaining additional data from both lab and witnesses as neededSlide48

Methodology

Assess the validity of the conclusions to a reasonable degree of scientific certainty, recognizing the limitations of science