Forensic Science SFS 1 Students will recognize and

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Forensic Science SFS 1. Students will recognize and classify various types of evidence in

Forensic Science SFS 1. 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).

ESSENTIAL QUESTIONS 1. What is forensic science? 2. What is evidence and how is

ESSENTIAL QUESTIONS 1. What is forensic science? 2. What is evidence and how is it used by forensic scientists? 3. What are the characteristics of a typical crime lab? 4. Which historical forensic scientists laid the ground work for modern forensic science? 5. What is the importance of Locard’s Exchange Principle?

ESSENTIAL QUESTIONS 6. What is the basic methodology used by forensic scientists? 7. What

ESSENTIAL QUESTIONS 6. What is the basic methodology used by forensic scientists? 7. What are the steps that must be followed in the pursuit of justice? 8. What is the importance of the Federal Rules of Evidence? 9. What is the importance of the Frye Standard? 10. What is the importance of the Daubert Ruling?

Forensic Science is… the application of science to those criminal and civil laws that

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 evidence

A forensic scientist… is a generic term for a professional or academic specialist in

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. ”

Professional and Academic Specialties Ø Criminalistics Ø Anthropology Ø Psychiatry and Behavioral Science Ø

Professional and Academic Specialties Ø Criminalistics Ø Anthropology Ø Psychiatry and Behavioral Science Ø Jurisprudence Ø Odontology Ø Engineering Sciences Ø Pathology/Biology (incl. medical, entomology, botany) Ø Questioned Documents Ø Toxicology Ø Digital and Multimedia Sciences

Laboratory Analytical Specializations Ø Chemistry (incl. toxicology, paint/polymers, instrumentation) Ø Computer Analysis Ø DNA

Laboratory Analytical Specializations Ø Chemistry (incl. toxicology, paint/polymers, instrumentation) Ø Computer Analysis Ø DNA Analysis Ø Explosives Ø Firearms and Toolmarks Ø Audio, Video, and Image Analysis Ø Latent Print Ø Materials Analysis (incl. mineralogy, metallurgy, elemental analysis) Ø Questioned Documents Ø Racketeering Records Analysis Ø Trace Evidence (incl. anthropology, odontology, hairs, fibers)

What do they do? A forensic scientist or criminalist’s primary job is to study

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.

Criminalists use laboratories to help them examine… EVIDENCE – anything that tends to establish

Criminalists use laboratories to help them examine… EVIDENCE – anything that tends to establish or disprove a fact • documents • testimony (oral or written) • exhibits • demonstrative (models, diagrams, photographs)

Crime Laboratories • There are nearly 400 crime labs in US – Federal, state,

Crime Laboratories • There are nearly 400 crime labs in US – Federal, state, county, and municipal (local) – Most function as part of a police department – Others 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 government

There is NO national system of forensic laboratories, nor is there a mandatory process

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 labs

 • Most labs are maintained by states for regional areas – GBI has

• Most labs are maintained by states for regional areas – GBI has 7 regional labs; – Eastern Regional Lab is located in Augusta and serves 15 counties

FBI Crime Lab Services • Biometric Analysis (DNA and latent print analysis) • Forensic

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)

GBI Crime Lab Departments • Chemistry (drug and fire debris, expert testimony, law enforcement

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)

GBI Crime Lab Departments • Operations Support (evidence receiving, entry into LIMS, evidence transport,

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)

Crime Lab Statistics • ~3. 8 million requests for services – Most were submitted

Crime Lab Statistics • ~3. 8 million requests for services – Most 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 analyses

Crime Lab Statistics • Employ over 14 k full-time personnel – Average salary for

Crime Lab Statistics • Employ over 14 k full-time personnel – Average salary for an analyst is ~$55 k/yr • Combined 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)

Federal Forensics Labs • Federal Bureau of Investigation – Terrorism, counterintelligence, cyber crime, public

Federal Forensics Labs • Federal Bureau of Investigation – Terrorism, 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)

Federal Forensics Labs • Drug Enforcement Agency – Drug-related crimes – HQ in Arlington,

Federal Forensics Labs • Drug Enforcement Agency – Drug-related crimes – HQ in Arlington, VA; 313 field offices (domestic and foreign) – Operated by the DOJ

Federal Forensics Labs • Bureau of Alcohol, Tobacco, Firearms, and Explosives – Crimes involving

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 DOJ

Federal Forensics Labs • United States Postal Inspection Service – Crimes involving the mail

Federal Forensics Labs • United States Postal Inspection Service – 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 Interior

 • Song Ci (1248) Founders of For. Sci – First written account of

• Song Ci (1248) Founders of For. Sci – First written account of using medicine and entomology to solve criminal cases • Purkyně (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

Locard’s Exchange Principle “Any action of an individual, and obviously the violent action constituting

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.

Criminal Justice and the Law US Constitution is the supreme body of laws that

Criminal Justice and the Law US Constitution is the supreme body of laws that trumps all • Statutory 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 applied

Criminal Justice and the Law • Civil Law (code law) – Collection of codified

Criminal Justice and the Law • Civil Law (code law) – Collection of codified statutes – Precedents are given less weight – Deals with relationships between individuals – More concerned with assigning blame than with establishing intent – “Preponderance of evidence” is required to convict

Criminal Justice and the Law • Criminal Law (penal law) – Body of rules

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

Types of Crimes A broken law is called a violation. • INFRACTION “regulatory offenses”

Types of Crimes A broken law is called a violation. • INFRACTION “regulatory offenses” – Least serious class of crime – Can be proceeded against without the right to a jury trial and/or indictment – Punishable by fines – Include traffic tickets/violations, jaywalking, littering, disturbing the peace

Types of Crimes • MISDEMEANOR – More serious class of crime than infraction –

Types of Crimes • MISDEMEANOR – More serious class of crime than infraction – Punishable by 1 year or less in prison, housearrest, probation, community service… – Include DUI, vandalism, petty theft (<$500), prostitution, public intoxication, disorderly conduct, trespassing…

Types of Crimes • FELONY – Most serious class of crime – Punishable by

Types of Crimes • FELONY – Most serious class of crime – Punishable by more than 1 year in prison or by death – Include kidnapping, arson, burglary, aggravated assault/battery, robbery, murder, grand theft (>$500), rape…

Criminal Justice and the Law • The forensic scientist, or expert witness, has an

Criminal Justice and the Law • 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.

The Frye standard (Frye vs. US, 1923) • Frye was convicted of murder. On

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 stated that scientific evidence must have gained “general acceptance” to be accepted in court – At that time, the deception test was not “generally accepted”…

The Frye standard – Commonly called the “general acceptance” test – Dictates that expert

The Frye standard – Commonly called the “general acceptance” test – Dictates 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 study

Federal Rules of Evidence (1975) • To be acceptable in court, evidence must be

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”

The Daubert standard (Daubert vs. Merrell Dow Pharmaceuticals, 1993) • Two families sued Dow

The Daubert standard (Daubert vs. Merrell Dow Pharmaceuticals, 1993) • Two families sued Dow claiming that childrens’ birth defects had been caused by mothers’ prescription drugs • The 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 FRE

The Daubert standard – The Frye standard was superseded by the Rules’ adoption –

The Daubert standard – The Frye standard was superseded by the Rules’ adoption – The judge is the “gatekeeper” and must evaluate the expert’s scientific knowledge based on the following criteria • • • Theory or technique can be/has been tested Subject to peer-review and publication Known or potential error rates Technique standardization Widespread acceptance within the field

The CSI effect • First reported in 2004 describing the effect of TV programs

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

The CSI effect • Jurors tend to expect more forensic evidence than is available

The CSI effect • Jurors tend to expect more forensic evidence than is available or necessary – Complaint from juror that the prosecution had not dusted the lawn for fingerprints OR • Jurors have greater confidence in forensic evidence than is warranted – Murderer acquitted despite eyewitness testimony

Steps in Pursuing Justice • Once a crime is committed and discovered… – A

Steps in Pursuing Justice • Once a crime is committed and discovered… – A suspect may be identified – Police investigate what may have happened – Information is collected – Crime 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 issued

Steps in Pursuing Justice • After a suspect is in police custody, s/he is…

Steps in Pursuing Justice • 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 Justice • After a defendant’s plea is made… – A preliminary

Steps in Pursuing Justice • After a defendant’s plea is made… – A preliminary hearing is conducted before a judge • This is to determine whethere is enough evidence to proceed to a trial • Probable 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 Justice • Pleading “not guilty by reason of insanity”… – Requires

Steps in Pursuing Justice • 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 crime – It removes the requirement to demonstrate intent

Steps in Pursuing Justice • A person is presumed innocent until proven guilty –

Steps in Pursuing Justice • A person is presumed innocent until proven guilty – The burden of proof rests with the prosecution – Only 50% of all arrests lead to conviction – Only 25% of all convictions are sentenced to 1+ years in prison

Steps in Pursuing Justice • Plea bargaining can reduce the burden on the court

Steps in Pursuing Justice • 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”

Methodology The Scientific Method does not and cannot work for the forensic sciences in

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.

Methodology 1. Acquire information about the incident of concern from primary witnesses 2. Anticipate

Methodology 1. Acquire information about the incident of concern from primary witnesses 2. Anticipate questions that others with vested interest in the incident will ask in the future • This requires experience and imagination

Methodology 3. Examine evidence with a focus on finding answers to the anticipated questions

Methodology 3. Examine evidence with a focus on finding answers to the anticipated questions 4. Compare the consistency of alleged events (hypothesis as proposed by the witness statements) with evidential data, obtaining additional data from both lab and witnesses as needed

Methodology 5. Assess the validity of the conclusions to a reasonable degree of scientific

Methodology 5. Assess the validity of the conclusions to a reasonable degree of scientific certainty, recognizing the limitations of science