Crime Scene Protocol Flashcards
What is the difference between a “primary” crime scene and a “secondary” crime scene?
The primary crime scene is where a crime actually occurred. A secondary crime scene is in some way related to the crime but is not where the actual crime took place.
How is an alibi useful when using deductive reasoning?
An alibi is proof that shows that a person wasn’t at the scene of a crime as the crime was being committed.
Explain how trace evidence is different from other types of physical evidence
Trace evidence is evidence that
At a crime scene, what is the role of police officers?
Police officers secure the scene.
At a crime scene, what is the role of the CSI unit?
Preserve the scene, interview witnesses, conduct systematic search for evidence, collect, preserves, and bag physical evidence, photograph the crime scene, evidence and bodies of the victims, take measurement of the crime scene, examine and collect trace evidence such as fingerprints, hairs & fibers, bodily fluids, etc.
At a crime scene, what is the role of the District Attorney?
What is the role of a medical examiner?
The forensic medical examiner may look into the deceased’s medical history, examine the crime scene and statements from witnesses, and analyze evidence found on the body, such as gunpowder residue or bodily fluids. Knowing other fields such as DNA, toxicology, and even ballistics is beneficial.
At a crime scene, what is the role of detectives?
What are the seven steps of crime scene processing in order?
- securing the scene -
- separating witnesses
- scanning the scene to determine where photos should be taken
- seeing the scene - Take photos of overall area and close ups, view should be taken at different angles and distances, close ups of evidence and bodies should be taken.
- sketching the scene
- searching for evidence
- securing the evidence
What is the purpose of separating witnesses before interviewing them?
To avoid having them discuss details of the incident with other witnesses.
To make sure to get as many details as possible about what events transpired.
What is the purpose of photographing and sketching a crime scene before collecting evidence?
Photographs taken at a crime scene allow investigators to recreate that scene for later analysis, or for use in the courtroom.
A rough sketch portrays the physical facts. It relates to the sequence of events at the scene. It establishes the precise location and relationship of objects and evidence at the scene.
What are the differences between a rough sketch and a final sketch of a crime scene?
Rough sketch: First pencil-drawn outline of the scene, location of objects and evidence within this outline. Shows all measurements, distances, furniture, doors, and windows, and the distance between objects, entrances, and exits, and victims. It is not drawn to scale, although distances are measured and indicated on the sketch. It includes report number, address of scene, sketcher’s name, time/date of creation. A final sketch is a finished rendition of the rough sketch. It is prepared for courtroom presentation and often will not show all measurements and distances originally recorded on the rough sketch. Only significant items and structures are typically present in a final sketch.
What is the purpose of using two fixed points to identify the location of evidence at a crime scene?
This method allows the specialist to measure all items of evidence from the first fixed reference point then move to the second fixed reference point to complete the measurements.
This method would be useful for long distance areas or multiple scenes spread over a large area.
Describe some methods that CSI unit members may use to carefully search for evidence.
The six patterns are link, line or strip, grid, zone, wheel or ray, and spiral.
The spiral search is used most often for outdoor crime scenes, is conducted by one person, and is done by walking in a circle from the outermost point of the inner perimeter toward the center of the circle. Strip method is when virtual strips or line are being imagined to walk through on the crime scene and look for the evidences. It is a good method for large indoors and outdoors crime scenes.
Explain the role of paper bindle, evidence bags, and the chain of custody in collecting evidence and documenting its handling.
Bindle paper is used for so-called trace evidence such as fibers, hair, paint chips, crystallized or dust-like material such as drugs, or other tiny particles. Tamper-proof evidence bags prevent mishandling and contamination when transporting samples and materials to the police station or lab for storage or testing.
Chain of custody refers to the process of maintaining and documenting the handling of evidence. It involves keeping a detailed log showing who collected, handled, transferred, or analyzed evidence during an investigation.
