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Unit 1 Observations/History. By the End of this unit you should be able to…. Define observation and describe what changes occur in the brain Describe examples of factors influencing eyewitness accounts of events Compare the reliability of eyewitness testimony with what actually happened
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By the End of this unit you should be able to…. • Define observation and describe what changes occur in the brain • Describe examples of factors influencing eyewitness accounts of events • Compare the reliability of eyewitness testimony with what actually happened • Related observation skills to their use in forensic science • Define forensic science • Practice and improve your observations • Sketch a profile from and observer • Know the major scientists in forensic science
Introduction • The forensic examiner must be able to find –identify the evidence • 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
Introduction • In general forensic science is the application of science to law • Forensic Science is the application of science to the criminal and civil laws that are enforced by police agencies in a criminal justice system.
Introduction • The main areas of forensic science according to The American Academy of Forensic Science are • Criminalistics • Engineering Science • General • Jurisprudence • Odontology • Pathology/Biology • Physical Anthropology • Psychiatry and Behavioral Science • Questioned Documents • Toxicology
Forensic Scientist • Most be proficient at the scientific method • Observe • Hypothesis • Data • Conclusion
History • The French were the first to apply a system for identification. • Alphonse Bertillon in 1879 • The Bertillon System (aka Anthropometry) • Take a series of body measurements to identify a person • Replaced by fingerprinting
History • Bertillon System • 11 different measurements • Height. Length of forearm and thickness of head • Each measurement was taken three times and averaged • After the age of 20; Bone dimensions do not change • Chance of two adults have the same value for two of the eleven measurements is 16 to 1 • Chance of two adults having the same value for all eleven measurements is 4,191,304 to 1
History • First case of Forensic science was used in third century China • Women claimed her husband died in an accidental fire. • Coroner noticed that there were no ashes in the husbands mouth • So he burned two pigs; one alive and one dead and check to see if there were ashes in the mouth • The alive pig had ashes the dead pig had no ashes
History • Fingerprinting was developed by a few different people • Francis Henry Galton is the first to find a definitive was to study and classify fingerprints • Wrote a book in 1892 which contained the first statistical proof supporting the uniqueness of his method
History • The most famous person in forensics was…. • Sherlock Homles • Not a real person • Created by Sir Arthur Conan Doyle • Popularized scientific crime-detection methods. • First to apply methods of serology, fingerprinting, firearms identification before it was accepted by real life criminal investigators.
History • Karl Landsteiner • In 1901 found that blood can be grouped in types • A,B,AB, and O • Leone Lattes • Devised a method to determining the blood group of a dried blood sample • Albert Osborn • Worked with documents and through his work we can use documents as evidence in the courtroom • Sir Alec Jeffreys • Developed the first DNA profiling test in 1984
History • Edmound Locard • Formal education was medicine and Law • Convinced the French Police to give him a lab in an attic • Only had a microscope and a spectrometer • Developed Locards Principle • When two objects come into contact with each other, a cross-transfer of materials occurs. • 1st Case he found coin counterfeiters because the metals in the coins matched the ones on the suspects clothes.
What is Observation? • Our brains can filter out information Point out some of the details in this photo
What is observation? • 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.
What is Observation? • Our brains apply previous knowledge to new situations • What assumptions can you make about this scene? How might those assumptions be wrong?
Observations by Witness • Are affected by: • Their emotional states • 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 • Reports from individuals about crime-scene events often vary • Observations depend on the level of interest, stress, 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
The Innocence Project • Barry C Scheck and Peter J Neufeld at the Benjamin N. Cardozo School of Law starting in 1992, use DNA to examine post-convictions cases. • The project has found that up to 87% of the wrongful convictions they discovered were due to faulty eyewitness identifications.
How to be a Good Observer • 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.
How to be a good observer • Turn off Filter • 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.
How to be a good observer • Leave the final interpretation of data until later – • Do look for patterns and make connections • But the more information obtained, the between will be the interpretations • Remember that eyewitness accounts and your own thinking can include prejudices.
How to be a Good Observer • Documentations • It is important to write down and photograph as much information as possible • Keep in mind that memory is faulty • Remember that our brains tend to automatically fill in gaps in our perceptions
OBSERVATION #1 Forensic Science Activity
Directions: • Observe the picture for exactly 30 seconds. Look at everything you think might be important. • After 30 seconds, answer the questions • How observant were you? Compare your answers to the picture.
Questions: • What time was it on the clock? • How many people were in the scene? How many males? females? • Describe the person at the front of the line. Was it a man or a woman? Was he or she wearing a hat? What kind of clothes was the person wearing? Could you tell how tall the person was? Did he or she have any distinguishing features? • What day of the month was it? • Did you notice anything unusual in the picture?
Observation #2 Forensic Science Activity
How observant are other people? • In the last exercise you may have forgotten some details, and remembered other things incorrectly. As you experienced, your own memory can sometimes fool you. But what about other people's memories? Try out this exercise to see how witnesses to the same scence remember different details. Think about how useful an individual's testimony can be. Does it help to have several witnesses to a scene?
Directions: • Choose several people to be observers and choose two people to be investigators. • Allow the observers to look at the picture for 30 seconds. The investigators should not look at the picture. • After 30 seconds, the investigators should begin questioning the observers. Each Investigator should question each observer. Then, the Investigators should attempt to reconstruct the scene based on the "eyewitness testimony".
Questions for Investigators: • Investigators can use these questions to guide their inquiry, but may also think of their own questions. • How many people were involved in the scene? • What can you tell about each individual's hairstyle, gender, approximate age, etc. • Was there anything unusual going on?
Wrap Up • Compare the comments that the observers made. How many details were mentioned? Did some statements conflict with other statements? In what way? Why?
Forensic Sketch Art Rendering from Eyewitness Description
Egg Heads • The basic shape of the head is egg shaped • One side rounded and the other more pointed • Draw a circle (top of the head • Draw an oval (forms the bottom of the jaw) • Connect them • Then adjust for proper face shape
Basic circle (red) and oval (yellow) Technique to create basic facial form (egg shaped)
Placing Facial Features • Find the center that is the placement for the eyes • Halfway between the eye position and chin is the position for the bottom of the nose • 1/3 of the way from the bottom of the nose to the chin is the lip line
Slightly above eye line draw in brow line/ arch • The eye is an oval • Two circles are contained in the eye are the Iris (the colored part) and the pupil
