Forensic Science

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Forensic Science

• Original Powerpoint Adapted from Richard
  SafersteinPrentice 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 lifes grimmest realities
  dispassionately while never losing sight of the
  feelings that keep her human

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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
• Doyles 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
• 1836 - James Marsh detected arsenic poisoning in
  connection with a criminal investigation
• 1839 - Mathieu Orfila, toxicology, perfected
  techniques to trace poisons
• 1879 - Alphonse Bertillon developed
  anthropometry, body measurements to distinguish
  individuals
• Late 1800s - 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

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History of Forensic Science

• 1910 Edmund Locard, exchange principle, 1st
  forensic science journal (Locards Exchange
  Principlestates 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
• 1980s 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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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 youre 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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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
• Arrestees clothing

5,040.00 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 its 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

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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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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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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 techniques 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 Experts 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