Introduction to Forensics - Unit 1 Study Guide

A comprehensive collection of flashcards covering key concepts in forensic science, essential for studying foundational principles and cases.

Goal of forensic science

To use scientific methods and techniques to analyze evidence in order to solve crimes and support legal cases.

CSI effect

A phenomenon where the portrayal of forensic science on TV shows creates unrealistic expectations about the speed, accuracy, and availability of forensic evidence.

Deductive reasoning

Drawing a specific conclusion based on general principles or facts.

Eyewitness reliability

Eyewitnesses can misremember details and be influenced by stress or leading questions, making their testimony unreliable.

Memory stages

Memory is formed in stages: Encoding → Storage → Retrieval

Memories can fade, be altered, or become distorted over time

Swiss cheese model of memory

Memories are incomplete and have gaps, which the brain tries to fill with assumptions.

Observation vs. Inference

Observation is directly using senses to gather information; inference is a logical conclusion based on observations.

The Bill of Rights

The first 10 amendments to the US constitution.

Sixth Amendment

Ensures citizens the right to a speedy and public trial, an impartial jury, to be informed of charges, and to have legal counsel.

Chain of Custody

It ensures that evidence is properly handled and documented to prevent contamination, loss, or tampering.

7 S's of Crime Scene Investigation

Secure the scene – Ensure safety and prevent contamination.

Separate witnesses – Prevent them from influencing each other.

Scan the scene – Identify points of interest and overall layout.

See the scene – Take photos/videos.

Sketch the scene – Create a detailed diagram.

Search for evidence – Systematically collect evidence.

Secure and collect evidence – Properly bag and label evidence.

Circumstantial evidence

Evidence that implies a fact but doesn’t directly prove it.

Direct evidence

Evidence that directly proves a fact, such as an eyewitness account.

Individual evidence

Evidence that identifies a specific person or object.

Class evidence

Evidence that narrows it down to a group.

Physical evidence

Non-living material found at a crime scene.

Biological evidence

Evidence that originates from a living organism.

Locard’s Principle of Exchange

“Every contact leaves a trace” - materials are transferred when objects come into contact.

Frye Standard

Evidence must be generally accepted by the scientific community to be admissible in court.

Daubert principle

Judges determine the admissibility of evidence based on testability, peer review, error rate, and acceptance by the scientific community.

Analytical skills

Skills involving examining evidence, identifying patterns, and forming conclusions, essential for solving cases.

Forensic Pathologist

Specialist who analyzes autopsies and determines cause of death.

Toxicologist

Specialist who analyzes drugs and poisons.

Odontologist

Specialist who analyzes dental records and bite marks.

Ballistics Expert

Specialist who analyzes firearms, bullets, and trajectories.

Case of Casey Anthony

Main evidence included decomposed body and duct tape; found not guilty due to insufficient evidence.

Case of JonBenet Ramsey

Key controversies included mismanaged crime scene; theories involved intruder or family involvement.

Jennifer Thompson and Ronald Cotton case

Thompson misidentified Cotton; DNA evidence exonerated him, highlighting issues with eyewitness reliability.

How do people process information/stimuli that bombards them on a daily basis?

The brain filters out unnecessary details and focuses on what seems important, which can lead to missing key details or misremembering events

Why is forensics important to society?

It helps solve crimes, ensures justice, prevents wrongful convictions, and increases public safety by identifying criminals and providing evidence for legal cases

Why is it so important that CSI, police, and all forensics scientists do not violate a person’s rights stated in the Bill of Rights?

Violating rights can lead to evidence being thrown out in court, wrongful convictions, or cases being dismissed

What is the purpose of the Innocence Project?

To use DNA evidence to exonerate wrongfully convicted individuals

How have forensic methodologies evolved over time?

Advancements in DNA analysis, fingerprint technology, and digital forensics have improved accuracy and efficiency

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

They establish a perimeter, limit access, and ensure safety while preserving evidence.

Example of circumstantial evidence

The suspect’s fingerprints are found on the knife used in the stabbing

- This suggests the suspect handled the weapon, but doesn’t prove they stabbed the victim

Example of direct evidence

A witness sees the suspect stab the victim.
- This directly proves the suspect committed the crime

Example of individual evidence

A fingerprint found at a crime scene that matches the suspect’s fingerprint
- Fingerprints are unique to an individual, so they can directly identify a specific person

Example of class evidence

A shoe print found at the crime scene that matches the size and brand of the suspect’s shoes.
- Many people may own the same type of shoe, so it can narrow down a group but not identify a specific person

Example of physical evidence

A broken window at a crime scene.
- It’s a non-living object that can provide clues about how the crime occurred

Example of biological evidence

Blood found on the floor next to the broken window

- It comes from a living source and can be analyzed for DNA to identify a person.)