Forensic Science: Observation Skills and Crime Scene Investigation

Core Responsibilities: A forensic investigator must clearly observe, interpret, and report physical evidence.
Brain Information Processing Flow: $\text{Sensory Information} \rightarrow \text{Attention} \rightarrow \text{Perception} \rightarrow \text{Short-term Memory} \rightarrow \text{Long-term Memory}$

How information is processed in the brain

Nature of Perception:
- The brain selectively absorbs sensory inputs and unconsciously applies cognitive filters.
- Paying attention to environmental details requires deliberate, conscious effort.
- Human perception is naturally limited, faulty, not always accurate, and may fail to reflect reality.

Variables Affecting Witness Accounts:
- Emotional states, stress levels, concentration, and interest level.
- Presence of surrounding people or animals, type/amount of environmental activity, and distractions.
- Personal prejudices, individual beliefs, motives, and the lapse of time since the event.
The Innocence Project:
- Founded in 1992 by Barry C. Scheck and Peter J. Neufeld at the Benjamin N. Cardozo School of Law.
- Uses post-conviction DNA evidence to definitively re-evaluate guilt or innocence.
- Discovered that flawed eyewitness identification contributed to up to $87\%$ of wrongful convictions.

Four Steps to Maintain Good Observation:
- Observe Systematically: Methodically scan a crime scene or microscope slide from section to section.
- Turn Off Filters: Act as a data-gathering system by consciously recording all details without bias.
- Avoid Premature Conclusions: Postpone evidence interpretation until every available detail is gathered.
- Compensate for Faulty Memory: Thoroughly photograph and document evidence to support expert testimony.
Objective Role of Forensics:
- Focuses strictly on uncovering physical evidence that stands as objective fact rather than proving suspect guilt.
- Requires analysts to clearly communicate scientific findings to convince a jury of reliability and accuracy.

Standard Investigation Protocol:
1. Secure the Scene: Isolate the area to protect evidence from contamination.
2. Separate the Witnesses: Prevent witness collaboration and narrative distortion.
3. Scanning the Scene: Assess and identify primary versus secondary crime scenes.
4. See the Scene: Capture visual evidence through crime scene photography.
5. Sketching the Scene: Construct accurate diagrams mapping evidence and physical layout.
6. Search for Evidence: Conduct structured searches using systematic patterns such as grid or outward spiral searches.
7. Secure and Collect Evidence: Properly package, label, and seal all physical evidence.

Theory Definition: Formulated by Professor Edmond Locard, it states that whenever an individual comes into contact with an environment, cross-transfer of physical material occurs.
Status of Evidence: Physical evidence cannot perjure itself, confuse events, or be absent; its value is diminished only by human failure to locate and interpret it correctly.

Overview: The unsolved murder of 6-year-old JonBenet Ramsey on December 25–26, 1996, in Boulder, Colorado, serves as a high-profile example of a compromised crime scene investigation.
Timeline of Key Events:
- Dec 24, 5:00 pm: John and Patsy Ramsey attend Christmas dinner at Fleet and Priscilla White's house.
- Dec 24, 9:30 pm–10:00 pm: The family returns home; JonBenet is put to bed.
- Dec 25, 12:00 pm: A neighbor hears a scream; another hears metal on concrete.
- Dec 25, 5:45 am: A 3-page ransom note signed "S.B.T.C" is found on the spiral stairs demanding $\$118,000.00$ ( $\$100,000$ in $\$100$ bills and $\$18,000$ in $\$20$ bills).