Forensic Science Introduction and Crime Scenes

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Questions and Answers

What must be maintained to ensure the integrity of digital images used in forensic documentation?

Public access to images

Image editing permissions

Chain of custody (correct)

A backup system for images

What should be ensured to confirm that an image has not been modified?

Images are reformatted for storage

Use of high-resolution cameras

Image continuity must be verified (correct)

Images must be deleted after use

What is essential to include when documenting a crime scene for court?

Initial assumptions made by investigators

Witnesses' personal opinions about the scene

Visual enhancements made to images

Environmental conditions and location details (correct)

Which type of media should be used for storing images to ensure they are not deleted?

WORM media (e.g., CD-R) Signup and view all the answers

When scanning a crime scene, what technology is mentioned as being widely available?

3D laser scans Signup and view all the answers

What must be created to track the use and access of digital images in forensic contexts?

An audit trail Signup and view all the answers

Which requirement must be met for digital imaging practices in the Criminal Justice System?

No captured images can be deleted Signup and view all the answers

What is one of the potential indicators of image alterations according to verification software?

Detection of tonal value changes Signup and view all the answers

Which detail is NOT necessary in a crime scene report?

Witness testimony Signup and view all the answers

What aspect of photography is essential for documenting a crime scene?

Shutter speed Signup and view all the answers

What information is crucial when noting the point and method of entry in a crime scene report?

Actions of the offender(s) Signup and view all the answers

Which detail should be included to maintain the investigative nature of a crime scene report?

Description of the scene Signup and view all the answers

When documenting a photograph of the crime scene, why is it important to record the direction of the photograph?

To provide context to the surrounding area Signup and view all the answers

What is an important factor to consider when noting items moved by the offender(s)?

Condition and location of the items Signup and view all the answers

In what way should statements prepared for court aim to communicate information?

Clearly what was seen and found Signup and view all the answers

Which type of information is least relevant for a crime scene analysis?

Opinions on criminal behavior Signup and view all the answers

Why is it critical that evidence be logged and signed for by individuals who transport or examine it?

To ensure continuity and maintain chain of custody Signup and view all the answers

What should be done if the packaging of evidence is compromised?

Reject the evidence and do not examine it Signup and view all the answers

Which information is NOT required on the label of collected evidence?

Content description of the evidence Signup and view all the answers

What is the purpose of creating contemporaneous records at a crime scene?

To assist in legal proceedings by depicting evidence collection moments Signup and view all the answers

Which of the following methods is NOT recommended for documenting a crime scene?

Writing notes after returning to the office Signup and view all the answers

In the context of evidence collection, what is the significance of tamper-proof tape?

It indicates whether anyone has accessed the evidence Signup and view all the answers

What type of sketches must be created at the crime scene?

Detailed sketches with accurate measurements Signup and view all the answers

Which of the following statements about evidence labeling is incorrect?

Evidence labels can be created later for convenience Signup and view all the answers

What is the main purpose of using a standard form for item examination by forensic providers?

To promote consistency and detail in the examination process Signup and view all the answers

What should be checked first when receiving an exhibit for examination?

The security and integrity of the packaging Signup and view all the answers

How should an exhibit be opened according to proper forensic procedures?

By cutting a new hole elsewhere on the package Signup and view all the answers

Why is it crucial to photograph the item upon receiving it in a significant orientation?

To aid in visual documentation of the item's condition Signup and view all the answers

What should be done with debris that falls from an item during examination?

Collect it and store it in a labeled Petri dish or grip seal bag Signup and view all the answers

What is the importance of collecting glass fragments during the preliminary examination?

They can be lost rapidly once the packaging is opened Signup and view all the answers

What is the purpose of the General Examination Record (GER) in the evidence recovery process?

To document the observations and actions taken during examination Signup and view all the answers

What should be done if the packaging of an exhibit shows signs of tampering?

Photograph the damage and make note of it in the GER Signup and view all the answers

What is the purpose of the Automated Fingerprint Identification System (AFIS)?

To provide an automated search of fingerprint records. Signup and view all the answers

How many identity records are contained in the national fingerprint (tenprint) database?

Approximately 8.3 million Signup and view all the answers

What happens after ridge details of a fingerprint are encoded and searched against the IDENT1 database?

Images are returned for the first 15 closely matching marks. Signup and view all the answers

What must an expert do to conclude an identification based on the fingerprint images?

Find sufficient features in agreement. Signup and view all the answers

What is the main function of fingerprint reagents in the analysis process?

To assist in the imaging of developed fingermarks. Signup and view all the answers

What factors should be taken into account when developing a fingermark?

The surface and environmental exposure. Signup and view all the answers

How is the conclusion of a fingerprint identification verified?

It is verified by two other experts. Signup and view all the answers

Which of the following describes a potential limitation during the analysis of fingermarks?

The analysis must be done non-destructively. Signup and view all the answers

What is primarily responsible for the general ridge patterns found in fingerprints?

Genetics Signup and view all the answers

Which fingerprint pattern is the most common?

Loop Signup and view all the answers

Which technique is used for enhancing latent fingerprints on non-porous surfaces?

Powder dusting Signup and view all the answers

In the case of the 'West Brother’s', what was the resolution to the confusion about the two individuals?

They had different fingerprints Signup and view all the answers

What percentage of fingerprints are classified as arches?

5% Signup and view all the answers

What is the purpose of fingerprint enhancement techniques?

To make fingerprints visible and distinguishable Signup and view all the answers

Which gland is primarily found in areas where fingerprints are located?

Eccrine sweat glands Signup and view all the answers

What is the main factor in determining which fingerprint enhancement technique to use?

The surface type and environment Signup and view all the answers

What is the result of the development process for latent fingerprints?

Chemical reactions yield colored or fluorescent products Signup and view all the answers

How do identical twins typically compare in terms of fingerprint patterns?

Their fingerprints differ Signup and view all the answers

Study Notes

Week 1 - Introduction and Evidence

Direct evidence establishes facts (eyewitness testimony or confessions).
Circumstantial evidence needs interpretation (e.g., DNA).
Locard's exchange principle: "every contact leaves a trace".
Eyewitness testimony has limitations (intentional blindness and change blindness).
Forensic science role: determining if a crime occurred, identifying suspects, supporting prosecutions, guiding police on prosecution success.

Week 2 - Crime Scenes

Crime scene: location of illegal act, where physical evidence is collected.
Crime scene investigators (CSIs): trained personnel collecting evidence.
Primary crime scene: where the crime took place.
Secondary crime scene: location related to the act but not the primary scene.
Investigation process: crime committed, reported, investigation, evidence preserved, analysis, conclusions, and prosecution.
Crime scene examination process: Preserve, assess, record, document, identify items of evidentiary value, and collect these items.
Crime types: Major (preservation of life, property, law & order, evidence, apprehension of offender) and volume (victim assistance, witness information, preservation of evidence, CSI request).

Week 3 - Documenting a Scene

CSI job number: initial of person recovering the sample.
Number of sample in sequence of recovery.
Label shows signatures of people handling.
Label shows chain of continuity of evidence (SOCO, etc.).
Label must detail movement of evidence from crime scene to lab, and court.
Signatures for evidence movement and examination.
All sides of packaging are sealed with tamper-proof tape.
Compromised packaging means no examination.
Label information must match log book.
Label must be attached with adhesive tape.
Information on label: suspect name/s, date of birth, and item information.
Location where evidence was found.
Date/time that evidence was collected.
Signature of person collecting evidence.

Week 4 - Documents, Fraud and Forgery

Documents: Include messages, written on surfaces, or on bodies.
Document examination reasons: Demonstrate authenticity, identify author/origin, establish if altered, contextual information.
Document examination: Handwriting (cursive/printing), signatures, typewriters/photocopiers/printers, alterations, additions, erasures, and obliterations.
Establishing authorship of a document: Analyzing handwriting, sequence, alterations, and content to discover inconsistencies.
Document authentication: Establishing a document's trustworthiness through security features like watermarks and fluorescent markers.

Week 5 - Fingerprints

Bertillonage (1883): Proposed anthropometry for identification (measuring body parts).
Limitations of Bertillonage: Identical names and characteristics could present inaccuracies from physical measurements.
Fingerprints: Ridge patterns persist throughout life and are unique.
Types of Fingerprints: Arch, Loop, and Whorl.
Fingerprint Classification: Categorisation based on patterns of fingerprints.
Fingerprints used for criminal identification.

Week 7 - Trace Evidence

Fingerprints: Traces left by contact between hands and surfaces.
Fingerprint techniques: Latent prints are invisible; need techniques to expose them.
Types of fingermarks and formation: Patent print (a visible print), Negative print (removes material from a surface), Plastic mark (an indentation).
Factors affecting fingermark formation: Fingertip/surface cleanliness (contamination), surface texture, and contact pressure/angle.
Preservation of fingermarks: Ensuring the evidence is not damaged or degraded.
Methods of developing/enhancing fingermarks: Chemical reactions, dyeing, stains, polymerisation, and more.
Fingermark imaging: Techniques for imaging and processing finger marks and examining them properly.
Fingerprint database: Large, UK-based database that allows for easy matching of prints.

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Description

Explore the fundamentals of forensic science, including types of evidence such as direct and circumstantial evidence. Understand the roles of crime scene investigators (CSIs) and the processes involved in crime scene examinations. This quiz covers essential concepts from the first two weeks of the course.