Analytical Forensic Science

The adventure Begins Now

What is Forensic Science?

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“Forensic”?

From Latin public (e.g. Roman Forum, or other fora, used for public matters)

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Public speaking, or public presentation of scientific evidence Today —science applied to legal issues

Why Take Forensic Science?

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CSI LV, NY, Miami….

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Because you were told to?

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Is it good, basic science?

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Is it applied science?

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Natural curiosity-The detective in all of us?

Forensic Science as a Career

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There are scores of forensic science programs (graduate and undergraduate) in the US —more each year

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Most do not lead to jobs….

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But —a good science background leads to a lot of good things

Disciplines in Forensics

       Life Science: anatomy, DNA, hair, bones Chemistry: toxicology, fibers, powders, paint, arson Physics: ballistics, blood spatter Geology; soil analysis, casts, mapping Math; statistics, graphing, measuring English; writing, reports, communication Social Studies: criminal law, justice

Forensic Science Lab Systems

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Federal —FBI, ATF, DEA, CIA, SecServ (Tres), Postal….

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State (CHP, CalDOJ) County, City Private labs (all sizes) Accreditation (no real rules)

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Some are and some are not

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ASCLD (www.ascld-lab.org)

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May affect quality, may not

Forensic Departments

       Physical Science experts Biologists-specifically DNA experts Ballistics Document examiners Photography unit and processing Toxicology and drug analysis Fingerprint lab

Forensic Jobs

      Serologist Prints examiner Anthropologist Entomologist Odontologist CSI    Trace evidence examiner  Firearms examiner  Tool mark examiner Pathologist Toxicologist  Document examiner

Fundamental Principle

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Edmond Locard (1900)

 “Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects. All of these and more, bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong, it cannot perjure itself, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value.”

Locard Exchange Principle

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Locard's exchange principle states that "with contact between two items, there will always be an exchange of material"

 The role of the criminalist is to link the suspect to the crime scene from this exchanged material

Expert Testimony

 The forensic specialist if often asked to testify in court on their findings.

 American justice system is adversarial (Prosecution vs. Defense)  Two significant rulings on the testimony of “expert” witnesses   Frye Standard The Daubert Ruling

The Frye Standard

 1923 James Frye convicted of murder  To meet the

Frye

standard, scientific evidence presented to the court must be interpreted by the court as "generally accepted" by a meaningful segment of the associated scientific community. This applies to procedures, principles or techniques that may be presented in the proceedings of a court case.

The Daubert Ruling

 1993 Daubert vs. Dow Pharmaceuticals  In

Daubert

, the Supreme Court held that federal trial judges are the “gatekeepers” of scientific evidence. Under the

Daubert

standard, therefore, trial judges must evaluate possible expert witnesses to determine whether their testimony is both “relevant” and “reliable”, a two-pronged test of admissibility.

Scandals in Forensic Science

    Fred Zain – Expert gone wrong Sandra Anderson – Planting evidence http://www.truthinjustice.org/ http://www.innocenceproject.org/