Flashcards
Forensic Science - Chapter 1
Flashcards do conjunto (64)
- 1Forensic science owes its origins to which individuals........Bertillon, Galton, Lattes, Goddard, Osborn and Locard.
(developed the principles & techniques needed to identify or compare physical evidence). - 2What is Forensic?1. pertaining to, connected with, or used in courts of law or public discussion and debate.
2. adapted or suited to argumentation; rhetorical. - 3What is Forensic Science?- application of science to criminal and civil laws.
-emphasizes the application of science to criminal and civil laws that are enforced by police agencies in a criminal justice system.
-Adversarial System - 4The CSI Effect.. What were the four problems ?1. Unrealistic Timeline
2. Sample Collection
3. Personalized Crime Scene
4. Conclusion of evidence - 5The 3 Fold Effect on Juries of the CSI Effect:1. Translation of Scientific Testimony for Juries
2. Juries Expect Better Results Than May Be Available
3. Views on Proper Investigatory Procedure - 6Scientificof a relating to the practice of science
- 7Inquirya close examination of a matter in a search for information or truth
- 8Scientific Inquirythe ways in which scientists explore the natural word
- 9Sciencea way of learning about the natural world
-includes all of the knowledge gained by exploring the natural world.
-the knowledge base is always growing and changing as scientists ask new questions and explore new ideas - 10Summarize the Scientific Method....-Ask questions
-Make observations / or influences
-Develop hypothesis
-Design experiments
-Make measurements
-Collect data
-Interpret data
-Draw conclusions
-Communicate those conclusions - 11HOW DOES SCIENTIFIC INQUIRY WORK?HOW DOES SCIENTIFIC INQUIRY WORK?
- 12Ask questions..Scientific inquiry begins with a question or a problem
- 13Make Observations and Inferences ...-Observations: using one or more of your senses to collect data
-Inference: an interpretation of an observation that is base on evidence or prior knowledge
-Data: facts, figures & other evidence gathered through investigation - 14Making Inferencesthis is only one of many possible interpretations of the observation.
- 15Developing Hypothesis-Hypothesis: a possible explanation for a set of observations or answer to a scientific question
-a hypothesis must be something that can be tested
-word as an IF....Then Statement
-can be either supported or disproved - 16Designing an experiment to test a hypothesis-after you state your hypothesis, you must design an experiment to test it
- 17Experiment Variables-Variable: factor that can change in an experiment
-Manipulated (independent) variable: variable that is changed during ur experiment
-Responding (dependent) variable: the factor that changes because of the manipulated variable - 18Controlled Experimentan experiment in which all of the variables except for one remain the same.
- 19Making Measurements and Collecting Data-Scientists have developed a standard system of measurement called The International System of Units (SI)
*why do scientists need a standard system of measurement? - 20Interpreting DataAfter data is collected, the data has to be organized and interpreted
*What are some ways to organize data so it is easy to understand? - 21Drawing Conlcusions-After the data os organized and interpreted you must draw a conclusion
*Does the data support your original hypothesis? - 22Communicating Findings-Scientists must communicate their finding to other scientist to contribute to the growth of the body of scientific knowledge
- 23Scientific Theory:a well-tested concept that explains a wide range of observations
-A theory is based on thousands of experiments done by different scientist
-Future testing may prove a theory to be incorrect - 24What Makes Science "Forensic"?An experiment result has no standing until it is disseminated to the rest of the scientific community
-by publication in peer reviewed journals
-allows for experiments to be repeated and results reproduced - 25What Makes Science "Forensic"? Continued......Data is generally not considered valid until it is reproduced by an independent source
-a product of the scientific community, not individuals - 26Review of forensic experiments...-another analyst in the laboratory
-an analyst assisting opposing counsel
-expert witnesses - 27Review is necessary-to catch clerical errors
-establish that conclusions are supported by data
-limitations: time, personnel, budget, equipment - 28FORENSIC METHODSFORESNIC METHODS
- 291. State a hypothesis ( What is the question?)I think the bullet found on the scene came from this gun found two blocks away- did it?
-You must be mindful of bias when formulating your question. Bias can cause the wrong question to be asked.
ex: how did OJ kill Nicole and Ron?
versus
did OJ kill Nicole and Ron? - 302. Design an experiment to test the hypothesis-compare the bullet microscopically with other test bullets known to have been fired from the gun
-the test bullets are the reference sample to which the crime scene bullet will be compared - 313. Make observations-photograph the bullet under investigation and the reference bullets through a microscope
-record the number of common features
-how many common features
-where are they located
-a general impression that they were the same or were not the same is not acceptable - 324. Experiments Include Standards and Controls:Controls:
-samples for which the results are known
-show that the experimental system is working properly
-properly calibrating a microscope so that the two bullets forced from the same gun can be matched up
Standards:
-devices with which the results of an experiment can be measured - 335. Analyze and Interpret the data-Once the data is collected, it must be analyzed
Bullet comparison;
Analysis-scrutinze the marks to determine if any difference between the questioned and known bullet are not relevant to the comparison - 346. Draw a conclusionAt the end of the experiment the data must be summarized.
Then a statement of the meaning or the data in the context of the hypothesis must be made:
-the number of similar marks are sufficient to declare that both bullets came from the same gun - 357. Define the next question-Getting answers to some questions
- Plan the next set of experiments
-Remember, in forensic, both time and sample are limited
-Often conclusions are drawn from only one experiment with limited data
-Its important to understand the limits of the systems being employed - 36CONTRIBUTORS TO FORENSIC SCIENCECONTRIBUTORS TO FORENSIC SCIENCE
- 37Mathieu Orfila a.k.a. MOThe father of forensic toxicology
- 38Alphonse Bertillion a.k.a. Al BDevised the first scientific system of personal identification in 1879
- 39Francis Galton a.k..a FrankConducted the first definitive study of fingerprints and their classification
- 40Leone Lates a.k.a LLDeveloped a procedure to determine blood type from dried bloodstains
- 41Calvin Goddard a.k.a. CalUse a microscope to determine if a particular gun fired a bullet
- 42Albert Osborn a.k.a. BertDeveloped the fundamental principles of document examination
- 43Walter McCrone a.k.a. WaltUtilized microscopy and other analytical methodologies to examine evidence.
- 44Hans Gross a.k.a GrossWrote the first treatise describing the application of scientific principles to the field of criminal investigation
- 45Edmond Locard a.k.a EdIncorporated Gross' principles within a workable crime laboratory
- 46Locard's Exchange PrincipleStates that when a criminal comes in contact with an object or person, a cross-transfer of evidence occurs.
- 47DEVELOPMENT OF FORENSIC TIMELINEPre-700 BC; Fingerprints are used on clay tablets for business transaction in ancient Babylon.
287-212 BC; Archimedes talks about being able to prove the crown was not made of gold using density and buoyancy - 48DEVELOPMENT OF FORENSIC TIMELINE250 BC; Erasistratus, an ancient Greek physician, discovers that his patients' pulse rates increase when they are telling lies. (Allegedly the first lie detection test).
- 49DEVELOPMENT OF FORENSIC TIMELINE1135; Story of Sung Tzu and the blood sickle. A murder was committed using a sickle. All those who owned a sickle were made to bring them out and lay them in the sun. Eventually flies gathered on one particular sickle, identify it as the murder weapon
- 50DEVELOPMENT OF FORENSIC TIMELINE1447; The missing teeth of the French Duke of Burgundy are used to identify remains.
- 51DEVELOPMENT OF FORENSIC TIMELINE1590; The first microscope developed by Zacharias Janseen of Holland
- 52DEVELOPMENT OF FORENSIC TIMELINE1609; Francis Damelle publishes the first treatise on systematic document examination
- 53DEVELOPMENT OF FORENSIC TIMELINE1686; Professor of anatomy Marcello Malpighi notes in his treatise the ridges, spirals and loops in fingerprints
- 54DEVELOPMENT OF FORENSIC TIMELINE1732; Luigi Galvani discovered that the human nervous system transmits information electronically
(lie detector) - 55DEVELOPMENT OF FORENSIC TIMELINE1807; Forensic Science Institute opened at the Univ. of Edinburgh, Scotland
- 56DEVELOPMENT OF FORENSIC TIMELINE1810; In Germany, the first document use of question document analysis occurs. A chemical test for a particular ink dye is applied to a document known as the Konigin Hanschritt.
- 57DEVELOPMENT OF FORENSIC TIMELINE1813; Matthew Orfila publishes his toxicology book and is considered the father of toxicology
- 58DEVELOPMENT OF FORENSIC TIMELINE1835; Henry Goddard of Scotland Yard first uses bullets comparison to catch a murderer. The comparison was based in a visible flaw in the bullet, traced back to a mold.
- 59DEVELOPMENT OF FORENSIC TIMELINE1836; Method for detection of arsenic poison developed by James Marsh of England (Marsh Test), the first use of toxicology in a jury trail.
- 60DEVELOPMENT OF FORENSIC TIMELINE1839; Dr. John Davy recounts experiments with dead soldiers using a mercury thermometer. One of the first attempts to determine time since death using body temperature.
- 61DEVELOPMENT OF FORENSIC TIMELINE1839; H. Baynard publishes the first reliable procedures for the microscope detection of sperm, and notes the different microscope characteristics of various different substrate fabrics.
- 62DEVELOPMENT OF FORENSIC TIMELINE1856; Sir William Herschel uses thumbprints on documents both as a substitute for written signature and to verify documents signatures.
- 63DEVELOPMENT OF FORENSIC TIMELINE1859; Spectroscopy was developed by Kirchoff and Bunson
- 64DEVELOPMENT OF FORENSIC TIMELINE1864; Ode