Observation & Documentation 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.

Our brains can filter out information. What is Observation? (click picture) Our brains can filter out information.

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. Memory itself is not like a video-recording, with a moment-by-moment sensory image. In fact, it’s more like a puzzle: we piece together our memories, based on both what we actually remember and what seems most likely given our knowledge of the world. The most striking demonstration of the minds’ guessing game occurs when we find ways to fool the system into guessing wrong. When we trick the visual system, we see a “visual illusion”—a static image might appear as if it’s moving, or a concave surface will look convex.  When we fool the memory system, we form a false memory.

What is Observation?

How observant are you?

Questions About Suspects Describe the picture in as much detail as you can. How many people are in the picture? What was the height of the tallest and shortest person? What colour shoes is the person with the tie wearing? What type of the hat is the person on the right holding? How many people have their hands crossed? 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

Eyewitness Accounts Eyewitness reports can vary significantly Barry C. Scheck and Peter J. Neufeld at the Benjamin N. Cardozo School of Law, starting in 1992, use DNA to examine post-conviction cases. The project has found that up to 87% of the wrongful convictions they discovered were due to faulty eyewitness identifications. Q. List what things may affect your observation or that of a person who witnessed a crime?

Eyewitness Accounts What What factors effects eyewitness observations? 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.

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 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.

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 better will be the interpretations. Remember that eyewitness accounts and your own thinking can include prejudices.

How to be a Good Observer? Documentation, documentation, documentation—

Summary The environment and our natural sensory filters affect our ability to observe. Eyewitness reports can be faulty. Gaining good observation skills is possible. Forensic scientists find, document, and accurately interpret the evidence.

Arriving at a Crime Scene The crime scene is first secured by a uniformed police officer. It is critical that no evidence is disturbed.

Arriving at a Crime Scene The scene is then most likely examined by the senior detective who is in charge of the investigation Specialist crime scene investigators (CSI’s) look for evidence.

Arriving at a Crime Scene Police photographer will take still photography and video. This can be used by forensic analysts or in court. Photos are taken from multiple angles using a forensic ruler

Arriving at a Crime Scene Often a police draughtsmen will sketch the site.

Arriving at a Crime Scene CSI’s wear gloves, overalls and overshoes to avoid contaminating evidence. A thorough search can take hours to ensure nothing is missed.

Removing the Evidence Evidence is “bagged and tagged” for analysis using Chain of Custody forms and evidence indicators.