forensic science

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

Observe, interpret, and report

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

Observation = factual info from senses; Perception = interpretation influenced by bias/experience

How does the brain take observations and process them?

Senses → Attention → Perception → Short-term memory → Long-term memory

What are the 4 lobes of the brain?

Frontal, Parietal, Temporal, Occipital

What is deductive reasoning?

Using facts and logic to draw a conclusion (general → specific)

How did the Daubert Standard differ from the Frye Standard?

Emphasized reliability and relevance of evidence

What effect did the Daubert Standard have on admissibility of evidence?

Broadened scope of admissible evidence

What broader trend does the evolution from Frye to Daubert reflect?

More rigorous and nuanced assessment of evidence

What are 5 criteria for being a good observer?

Pay attention to detail; Avoid assumptions; Record accurately; Be systematic; Avoid bias

What is an eyewitness?

A person who saw or experienced an event/crime firsthand

What is eyewitness testimony?

Statement in court by someone who personally witnessed the crime

What is the problem with eyewitnesses?

Memory can be faulty—stress, bias, and suggestion distort accuracy

What do forensic sketch artists do?

Draw suspects/crime scenes based on witness descriptions

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

Police; Detectives; CSIs; Medical examiner; Forensic specialists

Who founded the Innocence Project?

Barry Scheck and Peter Neufeld (1992)

What is the purpose of the Innocence Project?

Free wrongly convicted people and reform the justice system

What evidence does the Innocence Project often use?

DNA evidence

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

About 70% involve DNA evidence (per class material)

What document tracks who enters/exits a crime scene?

Crime Scene Log

Why is the Chain of Custody important?

Ensures evidence isn’t tampered with and is admissible in court

What are the 7 steps of crime scene investigation?

Secure; Separate; Scan; See (photos); Sketch; Search; Secure/Collect

Why should eyewitnesses be separated?

Prevents them from influencing each other’s memories

How is wet evidence collected?

Air-dried, stored in paper bags/envelopes

How is small, dry evidence collected?

In a bindle (druggist’s fold), then placed in envelope/container

How must bagged evidence with a signed seal be opened?

Open from a different location, reseal with new label/signature

What does “securing a crime scene” mean?

Make area safe, isolate, tape off, restrict access, start log

Difference between circumstantial and direct evidence?

Direct = proves fact directly (confession, video). Circumstantial = suggests fact (DNA, prints).

Circumstantial or Direct? a. Fingerprint on car handle b. Written confession c. Gum left at crime scene d. Tape recording admitting crime

a = Circumstantial; b = Direct; c = Circumstantial; d = Direct

What is a bindle?

A folded paper container for small trace evidence

Difference between individual and class evidence?

Individual = unique to one source (DNA, prints). Class = shared by group (shoe size, fiber).

Individual or Class? a. Skin cells/DNA b. Size 9 Nike shoe c. 1990 Ford Explorer d. Fingerprint on soda can

a = Individual; b = Class; c = Class; d = Individual

Difference between physical and biological evidence?

Physical = non-living (weapons, fibers). Biological = from living things (blood, DNA).

Physical or Biological? a. Jacket fiber b. Bullet casing c. Glass fragments d. Ransom note

a = Physical; b = Physical; c = Physical; d = Physical

During which CSI steps are evidence markers used?

Scanning and Seeing (photographs)

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

Created Locard Exchange Principle: “Every contact leaves a trace.”

What is the procedure for crime scene photography?

Wide shots → mid-range → close-ups (with/without scale), before moving anything

What type of photography is used in CSI?

Digital (sometimes film)

Criteria for photos in court?

Must be accurate, relevant, not misleading, and authenticated

What must be included in a crime scene sketch?

Case info, north arrow, scale, evidence labels, fixed points, legend

What are the types of sketches?

Rough sketch and Finished sketch

What is triangulation?

Measuring evidence location from 2 fixed points to form a triangle

Primary vs. Secondary crime scene?

Primary = where crime occurred. Secondary = related location with evidence.

What are the 4 goals of crime scene search?

Recognize, Preserve, Collect, Interpret evidence

What are the 4 search patterns?

Grid; Linear; Quadrant; Spiral

What is the importance of the Frye Standard?

First rule: scientific evidence must be “generally accepted” by experts

How is Daubert different from Frye?

Daubert = judge decides admissibility based on reliability/relevance

How has forensics changed over time?

From simple observation to advanced DNA, databases, digital forensics

What are the first 10 amendments called?

Bill of Rights

What does the 6th Amendment (Bill of Rights) guarantee?

Right to a fair and speedy trial, impartial jury, confront witnesses, have legal counsel

What does Article VI of the Constitution ensure citizens of?

Supremacy Clause (Constitution is supreme law; officials must uphold it)