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Original Powerpoint Adapted from Richard Saferstein Prentice Hall
Forensic Science Original Powerpoint Adapted from Richard Saferstein Prentice Hall and Mrs. Partridge LHS
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Definition fe-ren’ sik adj relating to, used in, or appropriate for courts of law or for public discussion or argumentation Latin forensis – public, of a forum forensic science is the application of science to criminal and civil laws.
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Criminalistics A body of knowledge concerning the recognition, collection, identification, individualization, and evaluation of physical evidence using the techniques of natural science in matters of legal significance.
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What a forensic scientist DOES!
She deals with life’s grimmest realities dispassionately while never losing sight of the feelings that keep her human Chair in the office of the world trade center Read the first few pages of the forensic science textbook about the DMORT member
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What a forensic scientist DOES
A forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences to the analysis of the many types of evidence that may be recovered during a criminal investigation. A forensic scientist may also provide expert court testimony.
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Is it “forensics”? The “science” of forensic science Scientific method
Observing Problem Researching problem – survey the scene Hypothesizing – who committed the crime based on evidence Testing – analyze the evidence to see if it implicates a suspect If answer is wrong, start over Avoid forming conclusions too early in an investigation. You may miss/neglect evidence.
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Is it “forensics”? Forensic Process R.I.I.R. Recognition
Scene survey, documentation, collection & preservation Identification Comparison testing Individualization Evaluation, interpretation Reconstruction Reporting & presentation -
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Scope of Forensic Science
Criminalistics – the application of physical sciences to criminal investigation Specialties Medicine Anthropology Odontology Entomology Legal Document analysis Ballistics Facial reconstruction others
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History of Forensic Science
Many believe that Sir Arthur Conan Doyle popularized scientific crime-detection methods through his fictional character Sherlock Holmes
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History of Forensic Science
Holmes applied new, developing principles of serology, fingerprinting, firearm ID, and questioned-document examination long before their value for first recognized and accepted by real criminal investigators Doyle’s first novel, A Study in Scarlet, has examples of his ability to describe scientific methods of detection, years before they were actually discovered and implemented
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History of Forensic Science
Forensic Science has been around nearly 900 years First recorded application of medical knowledge to the solution of a crime was in 1248 James Marsh detected arsenic poisoning in connection with a criminal investigation Mathieu Orfila, toxicology, perfected techniques to trace poisons Alphonse Bertillon developed anthropometry, body measurements to distinguish individuals Late 1800’s - Alexandre Lacassagne, ballistics and bloodstain patterns
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History of Forensic Science
1892 – Francis Galton developed methodology of classifying and filing fingerprints 1901 Karl Landsteiner discovered blood typing 1915 Leone Lattes devised a simple procedure for determining blood group Locard used only microscope and rudimentary spectrometer Exchange principle – when a criminal came in contact with an object or person, a cross-transfer of evidence occurred Case: 3 suspects and counterfeit coins. Asked police to bring the suspect’s clothing to his lab. Upon examination he located small metallic particles in all the garments. Chemical analysis revealed that the particles and coins were composed of exactly the same metallic elements. Confronted with the evidence, all three suspects were arrested and soon confessed to the crime.
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History of Forensic Science
1910 Edmund Locard, exchange principle, 1st forensic science journal (Locard’s Exchange Principle—states that when a criminal comes in contact with an object or person, a cross-transfer of evidence occurs) 1924 August Vollmer, LAPD crime lab (oldest) 1932 FBI laboratory, fingerprints 1980’s DNA testing ()
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Forensic Science in the USA
Federal (FBI, DEA, secret service, ATF) State (coroner, medical examiner) Local (sheriffs, police) Private (DNA labs) Stop/warn
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Coroner vs. Medical Examiner
Coroner – an elected official with death investigation duties Medical Examiner – an appointed government official, always a physician and often a forensic pathologist, with duties of investigating sudden and unexpected deaths or deaths from injuries
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Basic Services Provided by Crime Laboratories
Physical Science Unit (drugs, glass, paint, soil, explosives) Biology Unit (DNA, hairs, fibers, plants) Firearms Unit (ammunition) Document Examination Unit (handwriting, authenticity) Photography Unit (all photo; presentations for court)
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Optional Services Provided by Crime Laboratories
Toxicology Unit (drugs, poisons) Latent Fingerprint Unit Polygraph Unit Voiceprint Analysis Unit Evidence Collection Unit
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Envelope containing anthrax spores sent to Senator Tom Daschle shortly after 9/11. A variety of forensic skills used to examine it:
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Law and Science (see guided notes)
The philosophical foundation of the criminal justice system remains to PROTECT the innocent and to ensure that the TRUTH EMERGES for any matter before the court, thereby ensuring that JUSTICE IS DONE
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Bill of Rights The Bill of Rights was designed to expressly reserve certain powers to the citizens against the Federal Government The Bill of Rights was not always understood to apply to the rights of citizens when actions involved the state
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Precedent Cases Mapp v. Ohio, 1961: The 4th Amendment prohibits unreasonable searches Robinson v. California, 1962: The 8th Amendment protects against cruel and unusual punishment Gideon v. Wainwright, 1963: The 6th Amendment provides the right to counsel
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Application of the Bill of Rights
Amendments 1 through 14 apply to all states, saying: The Federal constitution provides the minimum protection. The state may provide greater protection but not less. ()
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4th Amendment The right of the people to be secure in their persons, houses, papers and effects against unreasonable search and seizures shall NOT be violated No Warrants shall be issued but upon probable cause, supported by an Oath or affirmation, particularly describing the place to be searched and the persons or things to be seized
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Presumptively Unreasonable!
4th Amendment The 4th Amendment requires that a valid warrant be issued prior to any search A warrantless search is Presumptively Unreasonable!
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4th Amendment A valid warrant is required for all unreasonable searches and seizures Required to obtain a warrant Probable cause Oath or affirmation Particular description area to be searched What you’re searching for
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Evidentiary Information
The probable cause clause requires that the police establish the trust worthiness of the information that they base their observations that a crime has been committed.
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Two Types of Information Sources
Citizen or victim Both are generally trustworthy No need to collaborate The informant Credibility of informant is important because informants may also be involved in criminal activity themselves
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Two Prong Test For An Informant
Reliability of information Established by identifying how, when, and where the informant received his information Credibility of the Informant Established by identifying the informant, determining his self-interest, & identifying the past accuracy of the informant
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Warrant Specificity The following must also be included on the warrant: Place - specific Time Items searching for Neutral authority – judges permission
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Area of Protection Areas of reasonable expectation of privacy:
Car Office House Abandoned property does not require a search warrant.
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$5,040.00 In Hidden Compartment
Warrantless Entry Consent Plain view Exigent circumstance Fire scene Belief that a person within is in need of immediate aid Cars parked in a public place Inventory of locked areas Caretaker Search incident to custodial arrest Arrestee’s clothing $5, In Hidden Compartment
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Chain of Custody Once the items have been seized and inventoried, chain of custody must be fully documented Specifies: who seized it, and every subsequent individual who has custody or control of the item
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Packaging of Evidence The CSI must make sure that the evidence is properly packaged according to the recommendations of the forensic laboratory When evidence is presented in court, it should be professionally packaged and presented It it’s necessary to repackage evidence, the original packaging must be included in or securely attached to the new package Not like this!
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Team Work Forensic scientists work as members of a larger team, perhaps other specialized scientists, law enforcement investigators, prosecutors, defense attorneys, judges, juries and the media.
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Law and Science Lawyers have an OBLIGATION to conduct a spirited defense of the accused, especially if they are guilty
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Law and Science In contrast, forensic science remains JUSTIFICATION based, reaching the truth, dependent upon evidence and data All scientists are required to uphold a high ethical standard, bound to combine scientific skills with a sworn duty to the public good
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Law and Science From crime scene to conviction, a good forensic scientist will be teaching others, an ability that requires patience and the communication of complex principles in simple terms.
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Law and Science Frye Standard
(named after the 1923 case) Requires the court to determine whether the scientific theory and/or scientific method used to generate evidence are generally accepted as reliable in the scientific community 1923 frye vs US rejecting the validity of the polygraph
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Law and Science Frye test:
Is the scientific theory generally accepted in the scientific community? (experts) Is the scientific method used generally accepted in the scientific community? (papers, books on the subject) Has the technique been applied correctly?
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Daubert v. Merrel Dow Pharmaceutical, Inc
Law and Science Daubert v. Merrel Dow Pharmaceutical, Inc Trial judges must assume the ultimate responsibility for acting as a ‘gatekeeper’ in judging the admissibility and reliability of scientific evidence presented in their courts
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Daubert Ruling Guidelines
Law and Science Daubert Ruling Guidelines Whether the scientific technique/theory can be (has been) tested Whether the technique/theory has been subject to peer review and publication The technique’s potential rate of error Existence & maintenance of standards controlling the techniques operation Whether the scientific theory /method has attracted widespread acceptance within a relevant scientific community
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An Expert’s Role By law, only a judge can declare someone an expert witness Attorneys offer an expert witness to the court to give opinions within their expertise Used to help clarify facts or educate the jury
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Court Advice For a Forensic Scientist
“Whereof one can not speak, thereof one must remain silent.” - Ludwig Wittgenstein
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