Introduction to Forensics

Forensic investigators must rely on their ability to ____, ____, and ____ observations clearly.

observe, interpret, report

What’s the difference between an observation and a perception?

Perceptions are made as a result of an observation

How does the brain take observations and process them?

It takes information from our senses and what we pay attention to rather than our perception and that puts it in our short term memory and only a few things go to our long term memory

Complete the following graphic organizer:

Information from our senses → what we pay attention to → perception → short term memory → long term memory

What are the 4 lobes of the brain?

1. Frontal Lobe

2. Parietal Lobe

3. Occipital Lobe 

4. Temporal Lobe

What is deductive reasoning?

Deriving consequences from facts using a series of logical steps

What are 5 criteria for being a good observer?

1. Make a conscious effort

   1. 5 senses

2. Observe everything slowly

   1. scan scene

3. make connections to observations

   1. relate observations to prior knowledge

4. don’t jump to conclusions

5. photograph and take notes

What is an eyewitness?

A person who has seen someone, or something, related to a crime and can communicate their observations.

What is eyewitness testimony?

when an eyewitness testifies in court about a crime

What is the problem with trusting eyewitnesses at a crime scene?

People’s memory can be influenced, molded, and manipulated

What do forensic sketch artists do?

Work with police to interview victims or witnesses of crimes in order to recreate a semi-realistic drawing that reflects the image of the perpetrator to the best of the witness’s memory.

List 5 people that might show up at a crime scene.

1. Police / possibility of a district attorney

2. crime scene investigators 

3. medical examiners

4. detectives

5. specialists

Who founded the Innocence Project?

Barry Scheck and Peter Neufeld in 1992

What is the purpose of the Innocence Project?

Uses DNA evidence to provide conclusive proof of guilt/innocence

What piece of evidence does the innocence project use to help set innocent people free?

DNA Testing

What percentage of wrongful conviction cases has the Innocence Project helped solve?

87%

What is the name of the document that showcases who has entered/exited the crime scene?

Chain of Custody

Why is the Chain of Custody important to follow?

To assure that the evidence is authentic when it gets to court

What are the 7 steps of crime scene investigation?

1. Securing the Scene

2. Separating Witness

3. Scanning the Scene

4. Seeing the Scene

5. Sketching the Scene

6. Searching the Scene

7. Securing and Collecting Evidence

Why should eyewitnesses be separated before they are interviewed?

To have an accurate testimony of what happened instead of the witness’s being influenced by each other’s stories or sharing false information.

How is wet evidence collected?

They must be air dried or placed in breathable packaging so they don’t mold.

How is small, dry evidence collected? ***

They are placed in a bindle to ensure the evidence doesn’t fall out.

If someone receives bagged evidence with a signature on a label, how must they go about opening the bag to get to the evidence?

They cannot break the seal so they enter through the bottom of the bag and once they’re finished analyzing the evidence they place the evidence in its original packaging and place it into another bag and seal it, sign it, and update the chain of custody.

What happens when a first responder “secures a crime scene?”

They make sure everyone in the area is safe and isolate the area to preserve and protect evidence. 

What is the difference between circumstantial evidence and direct evidence?

Direct evidence includes first hand observations and circumstantial evidence is indirect evidence that can be used to imply a fact, but not directly prove it.

Circumstantial or direct?

1. Fingerprint left on a door handle of a car - Circumstantial Physical

2. A written confession signed by a suspect - Direct

3. A piece of gum left at a crime scene - Circumstantial Biological

4. A tape recording of a suspect admitting to a crime - Direct

What is a bindle?

A druggist fold that ensures evidence doesn’t fall out during transport.

What is the difference between individual evidence and class evidence?

Individual narrows to one individual (DNA, Hair w/ the follicle) where as class narrows to a group of people/items (Shoe prints, blood type, hair w/o the follicle)

Individual or Class?

1. Skin cells found under the fingernails of a victim (DNA) - Individual 

2. Size 9 Nike shoe found beside a dead body - Class

3. 1990 Ford Explorer seen driving away from an armed robbery - Class

4. A fingerprint left on a soda can found at a crime scene - Individual

What is the difference between physical evidence and biological evidence?

Physical evidence is any object that can connect a suspect to a crime whereas biological evidence can tell DNA from blood, hair, or silvia. 

Physical or biological?

1. Jacket fiber (100% cotton) - Biological

2. Bullet casing  - Physical

3. Glass fragments - Physical 

4. Ransom note (not signed) - Physical

During which two steps of CSI are evidence markers used?

Why is Dr. Edmond Locard known as the father of forensics?

He established the first forensics laboratory in Lyon, France in 1910. Known for Locard’s Exchange Principle

What is the procedure for taking photographs at a crime scene? ***

Get overview shots of the entire scene, then mid range shots, and finally close up shots of the evidence while not disturbing the evidence as well as using scale markers at 3 different angles

What type of photography is used in crime scene investigation?

digital photography is the preferred method of crime scene photography

According to the justice system, what is the criteria for using photographs in court?

1. they must accurately reflect the true condition f the scene without alteration

2. any manipulations must be documented 

3. they must have relevancy (must support or undermine the truth of any point at issue)

What must be included in a crime scene sketch?

1. Triangulation

2. true north

3. legend or key

4. location

5. time and date

What are the different types of crime scene sketches?

1. Overview - a birds eye view or floor plan

2. elevation - portrays a vertical plane

3. exploded view or cross projection - a combination of overview and elevation

What is triangulation?

measuring the distance between the evidence and 2 fixed points

What’s the difference between a primary crime scene and a secondary crime scene?

1. Primary crime scene - the initial location

   1. a victim killed at their home

2. Secondary crime scene - a secondary location 

   1. killer disposed of a victim's body in woods after killing them at their home

What are the 4 goals of the crime scene search?

1. what has happened

2. who did it

3. how did they do it

4. why did they do it

What are the 4 crime scene search patterns?

1. Line/Strip

2. Spiral

3. Gird

4. Zone/Quadrant

What is the importance of the Frye Standard? ***

It's a legal test that determines the admissibility of scientific evidence and expert testimony in court.

How is the Daubert Standard different from the Frye Standard? ***

The Daubert Standard is flexible with an active judge and must have multiple pieces of evidence and is based on a specific criteria. Allows new scientific methods.

What are the first 10 amendments to the US constitution called?

Bill of Rights

What does Article 6 in the Bill of Rights ensure citizens of?

1. The 6th amendment gives citizens a series of rights in criminal trials

   1. the right to a fast and public trial by an impartial jury

   2. the right to be aware of the criminal charges

   3. the right to confront witnesses during the trial

   4. the right to have witness appear in the trial

   5. the right to legal representation