Forensic Evidence Collection Techniques

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Questions and Answers

What is a primary reason for avoiding sitting in a vehicle during examination?

To ensure tools are not left inside

To keep the seats clean for future use

To prevent the transfer of fibers from clothing (correct)

To avoid contamination with fingerprints

What type of evidence can marks be categorized as?

Evidence types such as footwear and fingerprints (correct)

Only marks made on hard surfaces

Only visible marks made by tools

Only shoe prints and tool marks

Why should you not attempt to fit a recovered tool into an instrument mark?

It could destroy the evidence in the mark (correct)

It may lead to misidentification of the tool

It risks leaving more marks on the tool

It may not fit correctly due to its age

What can enable almost any mark to be linked to the item that made it?

Forensic techniques that involve close examination Signup and view all the answers

What does the strength of the evidence from paint or glass depend on?

The material and circumstances of the case Signup and view all the answers

What is a consequence of two surfaces coming into firm contact with each other?

It leaves behind unique marks that can serve as evidence Signup and view all the answers

What role do unique characteristics of tools play in forensic investigations?

They can link a tool to specific marks on a surface Signup and view all the answers

What should you do if you see instrument marks at a crime scene?

Leave the marks untouched to avoid contamination Signup and view all the answers

What principle did Dr. Edmond Locard formulate regarding evidence at crime scenes?

Every contact leaves a trace. Signup and view all the answers

What role does trace evidence play in a criminal investigation?

It can link people or objects to various locations. Signup and view all the answers

How can contamination affect a crime scene?

It can create confusion about the sequence of events. Signup and view all the answers

What is the primary purpose of preserving trace evidence at a crime scene?

To maintain the integrity of the evidence for analysis. Signup and view all the answers

Which of the following can be considered potential types of trace evidence?

Biological materials like hair or skin cells Signup and view all the answers

What does careful examination of a crime scene aim to achieve?

Collection and analysis of trace evidence. Signup and view all the answers

What can trace evidence often serve as in a criminal investigation?

A starting point or lead for further analysis. Signup and view all the answers

Which of the following statements is true regarding the importance of trace evidence?

It can help establish connections between suspects and the crime scene. Signup and view all the answers

Which of the following media can fingerprints be found in?

Paper Signup and view all the answers

What should be done if broken glass at a crime scene cannot be protected from the weather?

Move it to a safe, dry place Signup and view all the answers

What is the unique characteristic of DNA in individuals?

It is unique to every person except identical twins. Signup and view all the answers

When retrieving items that may contain DNA, what should be done to prevent contamination?

Keep items away from likely contamination sources. Signup and view all the answers

How should broken glass be handled to preserve fingerprints?

Pick it up by the edges. Signup and view all the answers

Where can DNA be retrieved from?

From surfaces like cups and discarded clothing. Signup and view all the answers

Why is it important to inform the Scene Examiner or Crime Scene Manager when moving an article?

To ensure proper handling of all items. Signup and view all the answers

What type of acid is Deoxyribo-Nucleic Acid (DNA)?

Nucleic Acid Signup and view all the answers

What type of evidence is commonly linked with housebreakings and vandalisms?

Paint evidence Signup and view all the answers

Why is it crucial to recover clothing and footwear from a suspect quickly?

To prevent loss of paint and glass fragments Signup and view all the answers

What can cause contamination of contact evidence at a crime scene?

Unwitting interference by humans or animals Signup and view all the answers

What is one consequence if contamination of evidence occurs?

Scientific examination findings may be rendered valueless Signup and view all the answers

Which procedure should be followed regarding the transportation of victims and suspects?

They should not be transported in the same vehicles Signup and view all the answers

What happens to paint evidence in a road traffic accident?

It can transfer between vehicles or to victims Signup and view all the answers

Which of the following best describes evidence at crime scenes?

It can possess very high evidential value Signup and view all the answers

What is the primary risk when visiting a crime scene?

Cross-contamination of evidence Signup and view all the answers

What is one of the primary concerns when handling evidence at a crime scene?

Avoiding contamination of the evidence Signup and view all the answers

Which of the following is NOT one of the three phases of initial actions at crime scenes?

Collecting samples for testing Signup and view all the answers

Which entry should typically be made in a Scene Entry Log at a crime scene?

Weather conditions at the time of entry Signup and view all the answers

What should be a primary focus when preserving evidence at a crime scene?

Maintaining the integrity of the evidence Signup and view all the answers

What is a potential consequence of contamination at a crime scene?

Compromised evidence leading to wrongful conclusions Signup and view all the answers

Which of the following is an example of a health and safety consideration at a crime scene?

Using personal protective equipment (PPE) Signup and view all the answers

Why is it important to document entries in the Scene Entry Log?

To track the activities of all individuals at the scene Signup and view all the answers

Which type of evidence is critical to collect without delay?

Physical evidence that is vulnerable to loss or contamination Signup and view all the answers

Study Notes

Lesson Aim and Learning Outcomes

Aim: Explain evidential considerations within crime scenes.
Outcomes include explaining types of potential evidence, understanding contamination effects, identifying fingerprint sources, and noting initial actions and safety considerations.

Locard’s Exchange Principle

"Every contact leaves a trace" principle links people or objects to crime scenes.
Trace evidence is crucial for investigations, serving as initial leads.

Types of Potential Evidence

Trace Evidence: Links people or objects through materials like hair, fibers, and debris.
Fingerprints: Can be recovered from surfaces including glass, metal, and paper.
DNA Evidence: Unique to each individual (except identical twins), can be obtained from many items (e.g., cups, clothing).
Marks: Include tools and footwear impressions; can be matched to the items that made them.

Preservation of Evidence

Glass at crime scenes should be protected from contamination and handling.
DNA evidence requires avoidance of contamination, including not sitting in vehicles.
Instrument marks should not be tampered with; cover them if weather conditions might damage them.
Paint and glass fragments are lost quickly, necessitating prompt recovery from suspects.

Impact of Contamination

Contamination can significantly reduce the evidential value of contact evidence.
Strict protocols are advised to prevent contamination, such as not transporting victims and suspects together.

Initial Actions and Health & Safety Considerations

Identify three crucial phases upon arriving at a crime scene.
Maintain a detailed Scene Entry Log and crime scene notebook.
Follow Health and Safety guidelines to ensure personal and team safety during investigations.

Conclusion

Understanding evidential considerations is vital for successful crime scene investigations.

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Description

This quiz explores the important protocols for examining vehicles and the preservation of forensic evidence. Learn how marks and contact traces can play a crucial role in forensic investigations and the significance of unique characteristics in tools. Test your knowledge on best practices for collecting evidence without contaminating it.