Forensics Unit 1

The Seven S’s of Crime Scene Investigation

Securing the Scene, Separating the Witnesses, Scanning the Scene, Seeing the Scene, Sketching the Scene, Searching for Evidence, Securing and Collecting Evidence

Biological evidence

Biological evidence may make the group of suspects very small, or reduce it to a likely individual. (Body fluids, fingerprints, hair)

Circumstantial evidence

Most physical evidence reduces the number of suspects to a specific, smaller group of individuals (fingerprints, footprints, shoe prints, tire impressions, fool marks)

Class evidence

Narrows an identity to a group of persons or things(blood type of the suspect)

Crime scene

Any physical location in which the crime scene has occurred or is suspected to have occurred

Crime-scene investigation

recognizing, documenting, photographing, and collecting evidence from the crime scene

Deductive Reasoning

a logical approach where you progress from general ideas to specific conclusions

Direct evidence

First hand observations (Eyewitness accounts, police dashboard video cameras, witness testimony, confessions)

Eyewitness

person who has personally seen something happen and so can give a first-hand description of it

First responder

First to find out about the crime and deal with it. Their first priority is the safety of all individuals, second in to secure the crime scene.

Individual evidence

Narrows an identity to a single person or thing (fingerprint)

Observation

detailed investigation of incidents or crimes and verification of evidence that determines guilt or innocence

Opinion

a view or judgment formed about something, not necessarily based on fact or knowledge

Paper bindle

The paper bindle is ideal packaging for small, dry, trace evidence

Physical evidence

Most physical evidence reduces the number of

suspects to a specific, smaller group of individuals

Primary crime scene

the location where the crime took place

Secondary crime scene

a location other than the primary crime scene, but that is in some way related to the crime, where evidence is found.

Testimonial evidence

a statement made under oath

Trace evidence

the material left behind when two objects or people interact

Triangulation

verifying a participant's interview using observational field notes within a case study

Why are witnesses not allowed to talk to each other after a crime?

to avoid witnesses working together to create a story or a conclusion

What is the main purpose of photographing the scene?

To have a permanent way to make sure that nothing in the crime scene was changed more than it already was and to have everything immortalized to look back on

What kind of angles should photographs of evidence be taken from?

Photos of the overall area and close-up photos of evidence with and without a measuring ruler should be taken. A view of the crime scene should be taken from several different angles and distances. Several close-up photos of any evidence and bodies should be taken

What all must be listed on a final sketch for it to be usable in court?

1. notes the position of the body (if any) and any other evidence.

2. all obiects should be measure from two immovable landmarks.

3. north should be labeled

4. a scale of distance should be provided

- Final Copy

Computer programs are used to create a neater more accurate sketch suitable to use in a court proceeding.

What is the difference between a rough sketch and a final sketch?

A rough sketch doesn’t have accurately drawn measurements

Why does the rough sketch have measurements written on the paper, but a final sketch does not?

Because because the final sketch is 100% accurate in accordance to its key due to computer programs, but the rough sketch is drawn by a human hand

Why do you need to mark the camera locations on a crime scene sketch?

To explain what angles the camera captured when taking a picture of the area

Grid

Search used for large areas looking for a large object in two directions (Usually used with an arson investigation)

Linear

Search used for large areas looking for a large object in a single direction (Usually used at the site of a plane crash)

Quadrant/Zone

Search used for buildings or other structures (Usually used with homicides, home invasions, robberies, sexual assaults)

Spiral

Search used for large areas with no barriers, like an open field (Usually used with kidnappings, and homicide)

What is Locard’s Exchange Principle? Why is it important?

When a person comes in contact with an object or another person, a cross-transfer of physical material can occur. The intensity, duration, and nature of the entities and contact determine the extent of the transfer.

Who all makes up the crime scene investigation team?

police officers, detectives, crime-scene investigators, medical examiners, and specialists

What is the Innocence Project? Who created it?

exonerating wrongfully convicted individuals through DNA testing and other scientific advancements, and reforming the criminal justice system to prevent future injustice, made by Barry Scheck and Peter Neufeld