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Growth in Recent years is due to:
1) Supreme court decisions in the 1960s: “You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to speak to an attorney, and to have an attorney present during any questioning. If you cannot afford a lawyer, one will be provided for you at government expense.” Miranda vs Arizona, 1966 Greater emphasis placed on scientific evidence NOT on confessions!
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2. Increased crime rates over the past forty years.
(Chicago: 72% citywide increase in murders in 2016, from Jan 1st to present 523 deaths) 3. Increased # of drug cases since the 1960’s– drug cases now must be sent in for chemical analysis for tests before being used as evidence in court. 4. DNA profiling – very labor intensive with high technology requirements.
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The Federal government
Separate Major federal crime labs – none has total control: 1) The FBI 2) The Drug Enforcement Administration (DEA) 3) The Bureau of Alcohol, Tobacco, Firearms, and Explosives 4) The U.S. Postal Inspection Services 5) U.S. Fish and Wildlife Service
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Functions of the Forensic Scientist
Forensic Scientists rely primarily on scientific knowledge. However, only half the job is performed in the laboratory while the other half takes place in the courtroom. These functions fit into three categories:
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1. Analyzing Physical Evidence
Physical evidence is less likely to be compromised or tainted by human emotions than eyewitness accounts from victims, witnesses, or coerced confessions The analysis of physical evidence involves: adherence to strict guidelines systematic collection organization analysis of information An understanding of the admissibility of evidence is important
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2. Providing Expert Testimony
Forensic Scientist are called on to evaluate evidence when the court lacks the expertise to do so Must establish competency by citing educational degrees, number of years of occupational experience membership in professional societies, special courses taken and any professional articles or books published. Cross-examination may reveal weaknesses in background and knowledge Demeanor and ability to explain scientific data clearly and logically to a judge and jury of non-scientists Must be an advocate of truth and not take a side
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3. Providing Training Evidence must be properly recognized, collected and preserved if it is to have value. Many, but not all crime laboratories keep trained “evidence technicians”. Sometimes a patrol officer or detective collects the evidence. All officers engaged in fieldwork must be familiar with evidence collection. These people are trained by laboratory staff through extensive personal contact, lectures, laboratory tours and/or dissemination of manuals.
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Admissibility of Scientific Evidence
How does the court decide whether or not to accept scientific evidence? The judge and jury are typically not scientifically trained. Several court cases illustrate the steps in the development of admissibility.
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Frye vs. United States (1923)
Scientific validity of polygraph is rejected Court ruled that in order to be admitted as evidence in trial the questioned procedure, technique or procedure must be “generally accepted” by a meaningful segment of the scientific community. Collection of experts called in to testify about the validity of scientific issues Books and papers written on subject reviewed and discussed.
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Admissibility of Evidence
1923 Frye v. United States Scientific evidence is allowed into the courtroom if it is generally accepted by the relevant scientific community. The Frye standard does not offer any guidance on reliability. The evidence is presented in the trial and the jury decides if it can be used. Known as general acceptance standard. 1993 Daubert v. Dow Admissibility is determined by: Whether the theory or technique can be tested Whether the science has been offered for peer review Whether the rate of error is acceptable Whether the method at issue enjoys widespread acceptance. Whether the opinion is relevant to the issue The judge decides if the evidence can be entered into the trial.
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The Daubert Test Has the theory been tested?
The court suggested the trial court consider various factors to assess scientific validity Has the theory been tested? Has it been subjected to peer review by other scientists? What is the theory’s or technique’s known or potential rate of error? Do standards controlling the application of the theory or technique? Is the theory or technique generally accepted?
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Concerns about the Daubert Ruling:
Abandoning Frye’s general acceptance test will result in the introduction of absurd pseudoscientific claims in court Supreme Court rejected these concerns: The judicial system is capable Through vigorous cross-examination, presentation of contrary evidence and careful instruction on the burden of proof are the traditional & appropriate means of attacking shaky but admissible evidence. Different methods-same results
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