Observation vs. Inference Chapter 1 Observation Skills Forensic relating to the application of scientific knowledge to legal questions must have ability to observe, interpret, and report observations clearly. Observation what a person perceives using his or her senses. These are facts! Inference this is a "guess" using observations. on ntion e n rence rence nce e Introduction The forensic examiner must be able to find identify the evidence. no inferences/judgments are made at this point The forensic examiner must be able to document record the evidence. The forensic examiner must be able to interpret accurately determine the significance of the evidence. Go to Activity 1.1 Learning to See You will have 15 seconds to view each photo Our brains can filter out information. Point out some of the details in this photo. We are gathering information all the time. We are not aware of much of it because our brains filter it out. Why? Paying attention to the details requires a conscious effort. Perception interpreting information received from the senses. Mrs. Rynearson 1
Our brains fill in gaps in our perception. In order to make sense of what we perceive, our brains often enrich with detail what we see, taste, hear, smell, or feel. After an event, we can believe things were part of the background even though they were not. Our brains apply previous knowledge to new situations. i.e. a light pink food color is assumed to be strawberry We believe what we think we see and hear, even though the perception is wrong. What assumptions can you make about this scene? How might those assumptions be wrong? Observations by Witnesses are affected by: their emotional states. upset, happy, or depressed = more likely not to notice surroundings. fear and anxiety also interfere with accuracy whether they were alone, part of a group, or whether others were in the area. what type of and how much activity was going on around them. Eyewitness Accounts Eyewitness a person who has seen someone or something and can communicate these facts. Reports from individuals about crime scene events often vary. Observations depend on the level of interest, stress/emotions, concentration, and the amount and kind of distractions present. Prejudices, personal beliefs, motives, and any lapse in time since the occurrence can also have an affect. Eyewitness Accounts Memory fades with time and the brain fills in even more information that it deems appropriate even if it is not correct. Testimony of eyewitnesses is convincing to juries, despite its shortcomings. it is necessary to instruct jurors on the faults of eyewitness testimony. The Innocence Project Barry C. Scheck and Peter J. Neufeld at the Benjamin N. Cardozo School of Law, starting in 1992, use DNA to re examine post conviction cases. People already in prison, the group uses DNA evidence to provide conclusive proof of innocence or guilt. The project has found that up to 87% of the wrongful convictions they discovered were due to faulty eyewitness identifications. Mrs. Rynearson 2
Assignments Working in pairs 1) Research a person who has been proven not guilty by The Innocence Project. Write a short summary of the case including names of those involved circumstances of the case evidence used to convict specific evidence used to exonerate any other details of the case Assignments Working in pairs 2) When finished, complete the Digging Deeper assignment on pg 8. Go to http://school.cengage.com/forensicscience Click Launch Site Choose a chapter on the side of the page Click on the Digging Deeper box in the lower left Click any of the articles On the next site search for the Klump article and the Rossmo article. Go to Activity 1.2 You're an Eyewitness Fact vs Opinion Investigators must discriminate between fact and opinion Fact statement or assertion of information that can be verified Opinion personal belief founded on judgment rather than on direct experience or knowledge If someone is fleeing from a crime scene, what is your opinion? Witnesses Witnesses must describe what they saw, not what they think happened Investigators must then piece that info together the facts into a logical pattern conclusions drawn from assumptions and known facts. (inference) Those events must then be verified by the evidence 1.We do not naturally pay attention to all details Observe systematically Start at one part of a crime scene and run your eyes slowly over every space. Slowly look at every part of a piece of evidence. Do not assume that later on you will be able to remember everything. Mrs. Rynearson 3
2. We filter out unimportant information Turn off filters Do not pay attention to only what you think is important. On a crime scene you will not know what will turn out to be important. Make a conscious effort to pay attention to all the details in your surroundings. 3. We interpret what we see, look for patterns, make connections. Leave the final interpretation of data until later Do look for patterns and make connections. But the more information obtained, the better will be the interpretations. Remember that eyewitness accounts and your own thinking can include prejudices. 4. Our memories are faulty Documentation, documentation, documentation It is important to write down and photograph as much information as possible. Only evidence that is documented will be accepted; the verbal testimony of an forensic expert is not enough. Remember that our brains tend to automatically fill in gaps in our perceptions. Go to Activity 1.3 What Influences Our Observations Observations in Forensics What Forensic Scientists Do Forensic comes from the Latin, forensis, meaning "of the forum" where scholars could debate and discuss issues (like a court today) Forensic Science is concerned with uncovering evidence that stands as fact, not just whoever wins the debate. Lawyers debate in court by constructing a plausible story around the facts. Unlike TV, Forensic Scientists specialize in certain areas. Analytical skills ability to identify a concept or problem, isolate its component parts, organize information for decision making, establish criteria for evaluation, and draw appropriate conclusions Deductive reasoning deriving the consequences from the facts using a series of logical steps Mrs. Rynearson 4
What Forensic Scientists Do Study situations. Find clues in ordinary details. Work backwards from the evidence to what led up to the crime. Be patient. Practice. Chapter 1 Test tomorrow Case Studies and Career Questions due today Pg 13 14 # 1 15 due Wednesday Mrs. Rynearson 5