Crime Scene Processing and Documentation

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Questions and Answers

What is the primary source of physical evidence in a crime investigation?

Suspect's alibi

Laboratory analysis

Witness testimony

Crime scene (correct)

What is the purpose of marking evidence?

To identify and track the evidence (correct)

To destroy the evidence

To analyze the evidence

To store the evidence

What is the value of physical evidence in an investigation?

It is affected by public opinion

It can be impeached

It lies

It is not affected by sensationalism (correct)

What is the transfer of evidence theory?

Transfer of evidence from one surface to another Signup and view all the answers

What is the purpose of packaging evidence?

To preserve and protect the evidence Signup and view all the answers

What is an example of non-fingerprint impression evidence?

Shoeprint Signup and view all the answers

Who is responsible for the preservation and collection of evidence at a crime scene?

Officer-in-charge Signup and view all the answers

What is required to satisfy the integrity of evidence?

Four requirements must be satisfied Signup and view all the answers

What is the importance of documenting the location of evidence?

To record the location of evidence Signup and view all the answers

What is the purpose of an evidence receipt?

To record the transfer of evidence Signup and view all the answers

What is the primary objective of physical evidence in a criminal investigation?

To establish a link between the suspect and the crime scene Signup and view all the answers

When does the crime scene search typically begin?

After the initial walk-through of the scene Signup and view all the answers

What is the primary purpose of crime scene photography?

To provide a visual record of the crime scene Signup and view all the answers

Who is responsible for protecting the crime scene?

The crime scene investigator Signup and view all the answers

What is the transfer of evidence theory?

The exchange of evidence between two surfaces Signup and view all the answers

What is the primary use of a video camera in criminal investigations?

To document the evidence collection process Signup and view all the answers

What is the primary purpose of marking and packaging evidence?

To preserve the evidence for further analysis Signup and view all the answers

What is the primary purpose of a crime scene investigation kit?

To collect and preserve evidence Signup and view all the answers

What is an example of a type of physical evidence that can be found at a crime scene?

Shoe impressions Signup and view all the answers

What is the primary purpose of securing a crime scene?

To protect the crime scene from contamination Signup and view all the answers

What is the main objective of the 12 steps of a properly processed crime scene?

To collect and preserve physical evidence Signup and view all the answers

What is the purpose of sketching the crime scene in its original condition?

To create a visual representation of the crime scene Signup and view all the answers

What is an essential part of the crime scene investigation kit?

All of the above Signup and view all the answers

What is the purpose of the crime scene technician's equipment?

To identify, collect, and pack evidence Signup and view all the answers

Why is it crucial to maintain the chain of custody of physical evidence?

To make sure the evidence is not tampered with Signup and view all the answers

What can be used to protect fragile evidence found at the crime scene?

All of the above Signup and view all the answers

What is the primary responsibility of the first officer on the scene?

To protect the scene and preserve evidence Signup and view all the answers

What is an example of a type of non-physical evidence that can be found at a crime scene?

Witness statements Signup and view all the answers

What is the primary reason why trace evidence is often overlooked by the criminal?

The criminal thinks it has been successfully cleaned up or disposed of Signup and view all the answers

What is the main purpose of a crime scene search?

To look for clues and evidence Signup and view all the answers

What is the significance of the term 'trace evidence' in forensic science?

It refers to minute or microscopic bits of materials Signup and view all the answers

What is an example of transfer evidence that may be found on the suspect's clothing?

Fibers from the rug or furniture at the crime scene Signup and view all the answers

Why is it important to protect the crime scene immediately?

Because once the crime scene is lost, it's gone forever Signup and view all the answers

What is the primary reason why trace evidence is used in forensic science?

To link the suspect to the crime scene Signup and view all the answers

What is an example of transfer evidence that may be found on the victim's body?

Glass fragments from the vehicle Signup and view all the answers

What is the significance of the exchange of physical evidence during a crime?

It creates a link between the suspect and the crime scene Signup and view all the answers

What is the primary goal of a crime scene search in homicide cases?

To find physical evidence of the crime Signup and view all the answers

What is a characteristic of trace evidence that makes it useful in forensic science?

It is often overlooked by the criminal Signup and view all the answers

What is the primary purpose of a sketch at a crime scene?

To show the location and relationship of evidence items Signup and view all the answers

What is the purpose of triangulation in diagram methods?

To measure the location of evidence items from two or more fixed reference points Signup and view all the answers

Why is it recommended not to use scale in sketches unless the preparer is an expert?

Because the preparer may not have the necessary skills Signup and view all the answers

What is the primary tool used in a point-to-point search method?

Magnifying glass Signup and view all the answers

What is the purpose of a legend or key in a crime scene diagram?

To explain the symbols used in the diagram Signup and view all the answers

What is the purpose of dividing the search area into zones?

To ensure a thorough search Signup and view all the answers

What is the primary purpose of crime scene photography?

To provide a photographic record of the crime scene Signup and view all the answers

Why is it important to retain original sketches in crime scene investigation?

Because they may be needed in court Signup and view all the answers

What is the purpose of using a grid search pattern?

To search both interior and exterior areas Signup and view all the answers

What information should be placed on packaged evidence?

The officer's name, DSN, complaint number, and date Signup and view all the answers

Why is it important to maintain the chain of custody of evidence?

To establish the integrity of the evidence and demonstrate only authorized persons had control of it Signup and view all the answers

What is the purpose of using a spiral or circle search pattern?

To start from the center and move out in an ever-widening circle Signup and view all the answers

What is the purpose of using a strip search pattern?

To go back and forth across the scene Signup and view all the answers

What is the purpose of an evidence receipt?

To document the transfer of evidence from one person to another Signup and view all the answers

Why is it important to prevent cross-contamination of evidence?

To prevent the introduction of extraneous material that could compromise the integrity of the evidence Signup and view all the answers

What is the purpose of using a wheel search pattern?

To start in the center and move out in a straight line Signup and view all the answers

What is the purpose of using different evidence containers for different types of evidence?

To ensure the evidence is not contaminated Signup and view all the answers

What is the primary tool used in fingerprint equipment?

Brushes Signup and view all the answers

What is the purpose of using evidence seals and tags?

To mark evidence Signup and view all the answers

What is the primary tool used in a standard evidence kit?

Tweezers Signup and view all the answers

What is the primary purpose of using video in a crime scene investigation?

To supplement still photography Signup and view all the answers

What is the primary responsibility of the officer-in-charge of the crime scene?

To protect the crime scene Signup and view all the answers

What is a circumstance under which an officer may decide to move or remove evidence?

To prevent theft or contamination Signup and view all the answers

Why is it important to note the location of evidence on a sketch of the crime scene?

To facilitate identification of evidence in court Signup and view all the answers

What is a limitation of using photographs to record a crime scene?

All of the above Signup and view all the answers

What is the primary advantage of using sketches to record a crime scene?

They provide measurements and sizes of objects Signup and view all the answers

What is the purpose of maintaining a chain of custody for physical evidence?

To document the handling and storage of evidence Signup and view all the answers

Why is it important to properly mark or label evidence?

To facilitate identification in court Signup and view all the answers

What is the primary advantage of using video to supplement still photography?

It provides additional context and information Signup and view all the answers

What is the responsibility of the crime scene technician?

To process the crime scene Signup and view all the answers

What is the primary purpose of taking wide, general views of a crime scene?

To establish the location of the scene and orient the court and jurors Signup and view all the answers

What is the main reason for taking close-up photographs of evidence?

To record the condition of individual items before recovery Signup and view all the answers

Why is it necessary to include a measuring device in evidence photographs?

To provide a sense of scale and detail Signup and view all the answers

What is a key consideration for the admissibility of photographic evidence in court?

The photo must not be inflammatory or appeal to the emotions Signup and view all the answers

What is the purpose of taking photographs of the terrain adjoining the crime scene?

To establish the location of the scene and orient the court and jurors Signup and view all the answers

Why is it necessary to take multiple photographs of the same item of evidence?

To show the evidence with and without a measuring device Signup and view all the answers

What is the purpose of taking photographs of the point of entry and exit in a burglary scene?

To record the tool marks or other means of entry and exit Signup and view all the answers

What is a key consideration for the photographer when taking photographs of a crime scene?

The photographer must be able to state the photo is a true representation of the scene Signup and view all the answers

What is the purpose of taking photographs of the burn patterns in an arson scene?

To record the point of origin of the fire Signup and view all the answers

Why is it necessary to follow proper chain of custody when handling photographic evidence?

To prevent the evidence from being contaminated Signup and view all the answers

Study Notes

Introduction to Crime Scene Processing and Documentation

The course covers the elements of crime scene processing, including identifying sources of evidence, search methods, collection, preservation, marking, and packaging of evidence.
A practical exercise will be conducted to simulate crime scene processing, including searching for evidence, diagramming the scene, and explaining how to handle evidence.

Physical Evidence

Physical evidence is any solid, semi-solid, or liquid material that aids in determining the truth during an investigation.
It is used to show the presence or identity of a suspect and the opportunity to commit the crime.
Examples of physical evidence include:
- Fingerprints
- Weapons
- Bullets and spent casings
- Blood and other body fluids
- Hair and skin scrapings
- Clothing and fabric threads
- Impressions (shoe, tire, tool marks, teeth)
- Tools
- Drugs
- Glass and wood chips
- Paint and paint chips
- Soil and grass
- Documents (letters, notes, checks)
- Bindings (cord, tape, wire, chain)
- Unknown liquids (poison, liquor, flammable)
- Cigarette butts
- Explosive devices

Main Sources of Physical Evidence

The main sources of physical evidence are:
- Crime scene
- Suspect
- Victim

Transfer of Evidence Theory

The transfer of evidence theory states that when two surfaces come into contact, there is a partial transfer of material from one surface to the other.
Examples of transfer of evidence include:
- Fibers from clothing to surfaces
- Fingerprints to surfaces
- Blood or hair from one person to another
- Glass fragments or small paint chips from a vehicle to a pedestrian

Trace Evidence

Trace evidence is small particles of evidence that are often overlooked by criminals.
It is used to establish an offender's identity and link them to a crime.
Examples of trace evidence include:
- Fibers from clothing
- Hair
- Blood
- Glass fragments
- Paint chips

Crime Scene Searches

A crime scene is the place where the crime occurred, plus any adjoining entry and/or exit points.
The main purpose of the crime scene search is to look for clues and evidence and to reconstruct the crime.
The search for evidence begins with the effective protection of the crime scene.
Methods of sealing off the crime scene include:
- Police line tape
- Rope
- Barricades
There are 12 steps to a properly processed crime scene:
1. Approaching the crime scene area
2. Protecting the crime scene
3. Removing and separating witnesses
4. Conducting a preliminary survey of the crime scene
5. Writing a narrative description of the crime scene
6. Photographing the overall crime scene and physical evidence
7. Sketching the crime scene in its original condition
8. Processing the crime scene for latent impressions
9. Conducting a detailed search of the crime scene
10. Collecting, recording, marking, and preserving physical evidence
11. Packaging and transporting physical evidence for expert examination
12. Maintaining the chain of custody of physical evidence up to the time of trial

Crime Scene Investigation Kit

A crime scene investigation kit typically includes:
- Vehicle equipment (spotlight, hand-held axe, shovel, etc.)
- Camera equipment (camera, strobe/battery pack, extra batteries, etc.)
- Containers (bags, envelopes, etc.)
- Evidence kit (tweezers, scribe, metal inspection mirror, etc.)
- Documents (maps, notebooks, search warrant forms, etc.)

Search Methods

There are several search methods, including:
- Point-to-point search
- Strip search
- Grid search
- Zone search
- Spiral or circle search
- Wheel search
Each search method is used for specific types of crime scenes and areas.

Crime Scene Photography

Crime scene photography is used to:
- Supplement notes and sketches
- Clarify written reports
- Provide a permanent record of fragile or perishable evidence
- Aid in the identification of people
Photographs should be taken in a specific order, including:
- Wide (general) view
- Medium view
- Specific crime scene pictures
- Close-up view
Photographs should include scale, ruler, tape measure, inch marker, or yard stick for reference.### Photographing Evidence
Two photos should be taken: one with and one without a measuring device
Officers can use a business card with a "ruler" printed on the reverse side as a measuring device
Photographs can be used to clarify the physical evidence appearance of an item that would be otherwise hard to describe
Photographs can reproduce shoe, tire, and similar impressions which can be recorded in no other way

Admissibility of Photographs

The item pictured must be material, competent, and relative to the point in issue
The photo must not be inflammatory or appeal to the emotions or tend to prejudice the court or jury
Judges may suppress photos of mutilated bodies, blood-stained clothes, or human genitalia
The photos must be free from distortion and not misrepresent the scene
The photographer or other witness must be able to state the photo is a true representation of the scene
Proper chain of custody must be followed

Video Recording

Video is an additional resource to use for recording and documenting a crime scene
Video cannot replace still photography but can supplement the investigator's work
Video is typically used to record crime scenes, re-enactments, and confessions

Evidence Collection

The proper discovery, collection, and handling of evidence is necessary for the evidence to be used in a case investigation and prosecution
Always remember to put the time, date, location, and your initials on every piece of evidence
Care must be taken when collecting physical evidence so that it will retain its original condition and not be altered or damaged
There are four things that must be done to properly maintain the integrity of physical evidence:
- Maintain it in its original state
- Maintain a chain of custody
- Properly package the evidence
- Properly mark the evidence

Evidence Collection (continued)

The officer assigned to the crime scene is responsible for the preservation and collection of evidence
Evidence should be left where found until processed, but it may be moved or removed under certain circumstances (e.g. safety factors, possibility of theft, weather contamination)
Specialized crime scene units may be summoned for any scene that needs to be processed
Evidence must be properly marked or labeled for identification as soon as practicable

Recording a Crime Scene

There are various ways to record a crime scene:
- Notes: contain a great deal of information, but require great detail
- Photographs: record every detail, but don't give distances or sizes of objects and can be cluttered and confusing
- Sketches: provide measurements, sizes, and distances, and show only relevant objects, excluding unnecessary details
Diagram methods:
- Triangulation: used for outdoor scenes, requires two or more fixed reference points
- Projection: includes total crime scene with all objects of interest in the area
- Cross-projection: used for interior scenes, diagraming walls, windows, and doors

Marking Evidence

Evidence is marked so that it can be identified at a later time, such as in court
The generally accepted method of marking evidence is to place the officer's initials and DSN on an inconspicuous part of the evidence
Items which cannot be marked (e.g. hair, liquids, drugs) should be placed in an appropriate evidence container with the officer's initials and DSN on the container

Packaging Evidence

The purpose of packaging evidence is to ensure that it will retain its original condition until it is processed by the crime scene laboratory or is presented in court
Evidence gathered from different sources (e.g. scene, suspect, victim) must be packaged separately to prevent contamination
Commonly used evidence containers:
- Cardboard boxes
- Evidence bags
- Pill boxes
- Coin envelopes
- Paper bags
- Plastic bags
- Mason jars
- Plastic bottles
- Weighing papers
- Handgun envelopes
- Metal cans
Information that should be placed on packaged evidence:
- Officer's name and DSN
- Complaint number
- Victim's name
- Suspect's name
- Date
- Contents
An evidence receipt should be prepared any time evidence is tagged or packaged

Transporting Evidence

The custody of the evidence must be traced for every person who had possession of that evidence from seizure to court disposition
Evidence may be transported to and from the lab, agency, court, etc.
Always get a receipt when you turn evidence over to anyone

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Description

This quiz covers the basics of crime scene processing, including identifying evidence sources, search methods, and evidence collection and preservation. A practical exercise is included to simulate crime scene processing.