Methods In Crime Scene

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UV

-found in 2 forms: -short-wave UV (100-280nm) -long-wave UV (315-400nm) -One of the original forms of ALS used in forensic work. -Allows better visualization by increasing contrast with the substrate either by absorption or fluorescence

The Crime Scene Sketch

-graphically illustrates the layout, orientation and interrelationships of the scene and evidence. -The standard _________ is drawn as a "bird's eye view"/"overview" -The the jury and you -Acts as a filter

Triangulation Mapping, Regular Shaped Items:

-have fixed shapes that will not change with movement. -Require a total of 4 straight line measurements from 2 distinct landmarks in the room to 2 distinct points on the ite. -This fixes the item in a very specific position in the scene.

Ultra Violet

(200-400nm - no filter)

Infrared

(800nm - visible light filter)

Broadband Blue Light

- Varying wavelengths depending upon manufacturer, typically in the 415-455 range, orange, yellow filters

Sketch teams require 3 individuals:

-2 take measurements -One annotates the sketch and take notes -In a pinch, 2 can do the job, but be careful, as notes and measurements get mized up.

Baseline Mapping

-A single measurement is made from the evidence to the __________ at a right angle. -Inappropriate for typical interior scenes.

A written record of photos, detailing:

-Administrative Data -What time the photos were takenand in what order, -What they show -Other pertinent details as deemed necessary

Evidence Close-Up Photographs

-Are exposed with a "macro" lens (50mm, 55mm, or 105mm). -Function is to allow the viewer to see all evident detail on the item of evidence. -You have to get close and fill the frame with the evidence itself. -They are taken with and without a scale.

Overall Photographs

-Are exposed with a wide angle lens or in a fashion that allows the viewer to see a large area in the scene. -Their function is to document the condition and layout of the scene as found -They help eliminate issues of subsequent contamination -Typically taken by shooting from the 4 corners of the crime scene - will often capture the entire scene - if not, additional ones need taken from an appropriate vantage point can be taken.

Evidence Establishing Photographs

-Are typically exposed with a 50mm lens -Function is to frame the item of evidence with an easily recognized landmark. -Most overlooked in crime scene work -Is not intended to show details, simply to frame the item with a known landmark in the scene. -The close up and __________ go hand in hand.

Media Issues

-Assessment involves aspects of dealing with the ______. -Are often viewed in an antagonistic fashion by the crime scene investigator -Use caution when dealing with the media, but treat them as professionals. -Police are the gate-keepers. We decide how much access to allow and what info to release. -Don't speculate, don't lie and if you're not prepared to release info, then say no. -Assign experienced officers as the PIO and then work as a team to decide what info to release.

The most common mapping methods include:

-Baseline Coordinates -Rectangular Coordinates -Triangulation -Polar Coordinates -Triangulation or Rectangular Coordinates on a Grid -Triangulation on a Baseline

Why are search teams a matter of circumstances, but always require a minimum of 2 individuals

-Because no two people survey or perceive the same way, so two sets of eyes prevents items from being overlooked.

Baseline Mapping

-Best utilized in exterior scenes with limited landmarks. -Is extended from a datum point in a cardinal direction (N,S,E,W)

Triangulation Mapping

-Best utilized in scenes with evident landmarks -The most precise mapping method as it fixes regular shaped objects in a specific position -It is time intensive due to the measurements required -The number of measurements is based on whether the objects shape its regular or irregular

A variety of hazards to the crime scene technician exist in the scene. These include:

-Bio-hazards from blood or body fluids -Structural hazards in fire and explosion scenes. -Chemical and inhalation hazards in fire scenes. -Inhalation and chemical hazards in fire scenes from on-scene processing techniques. -Inhalation and explosion hazards associated to drug labs. -Bio-chemical hazards associated with terrorism.

There are 5 basic crime scene search patterns:

-Circle Search -Strip or Line Search -Gird Search -Zone Search -Point to Point Search

Cross Projection Sketch

-Combines both the "birds-eye" and "elevation sketch -Simply lay down the walls -Shows the relationship of both vertical and horizontal planes

2 Basic Documents of Written Narrative:

-Created during crime scene investigation 1.) Crime Scene Notes 2.) Crime Scene Report

RUVIS

-Developed for imaging -involves short-wave UV light that is enhanced using an intensifier (similar to that used in early forms of night vision devices) -Effective for locating and photographing undeveloped latent prints -Effective in some instances for shoe marks

Photograph Methodology

-Document the entire scene in-situ as soon as possible using overall photographs. -Photograph all fragile evidence as soon as possible. -In the documentation stage, photograph all known evidence using evidence establishing andevidence close-up photos -As items are discovered in later stages, return and document them fully, including additional, overall photographs if needed. -Create photographs that fully demonstrate the results of additional examinations -Always use a film roll reference card on the first shot of each roll to demonstrate admin data. -Always use a crime scene photo log

Elevation Sketch Drawing

-Drawn as a "side view" -Demonstrates items on vertical planes

Typical Sketch Drawing

-Drawn in a "bird's eye view" (horizontal) -Easily demonstrates items in a horizontal plane.

Crime Scene Hazards

-Each scene myst be assessed for any obvious __________ -Any risks associated to the _______ should be mitigated, if possible, before exposing team members to the ________. -The use of personal protective equipment (PPE) will mitigate or reduce exposure to many common _______.

Strip Search

-Excellent in exterior scenes where a large area must be examined. -Visual alignment to the ______ is good for most situations, but as the area to be searched grows, it becomes more difficult to maintain a visual reference of the lanes -Physically laying out the ________ with string or tape can help maintain the order.

Circle (Spiral) Search

-Excellent pattern in most interior or confined exterior scenes -Not effective in large exterior scenes or cluttered areas that impact on the __________ movement -Searcher moves inward or outward from a starting point.

Environmental Conditions

-Extreme heat or cold can affect the ability of the searcher -Wind, rain, fog and other factors may also impede the searchers ability -Any of these conditions may demand narrowing the search swathe to preclude missing items.

Controlling Light

-Good lighting is a must and is often missing in crime scenes -The best advice is to use fill-flash techniques -This reduces shadows and ensures sharp detail. -Watch for over exposure when taking close-up photographs with fill-flash (diffuse the flash with bounce lighting, a diffuser, or by using off camera flash methods.

Physical Control of the Camera: (2 handed grip)

-Good photography starts with a stable camera -At shutter speeds 1/60th of a second and higher, the investigator can hold the camera. -At shutter speeds 1/30th of a second or less, a tripod is necessary. -Some close-up work will result in better photos when you use a tripod at shutter speed.

Triangulation Mapping, Irregular Shaped Items:

-Have a ___________ with no specific points or shapes that will change with movement. -Require 2 straight line measurements from 2 distinct landmarks in the room to the center of mass on the item. -This fixes the item as effectively as possible in the scene

Crime Scene Teams

-Have to be manned appropriately, difficult to manage crime scene activity if under staffed. -Different stages of the processing methodology demand different levels of minimum manning.

The formal sketch, whether hand drawn or computer generated, has 5 basic elements. What are they?

-Heading -Diagram Area -Title Block -Scale and Direction Notations

Crime Scene Photo Log

-Helps eliminate many of the issues discussed.

Crime scene photography has 4 recurring problems that detract from its value. These are:

-Identification Issues -Orientation Issues -Confusion Issues -Incomplete Documentation Issues *Any one of these issues can detract from the viewers understanding of the scene.

The Crime Scene Report should be organized into functional parts include:

-Introduction -characteristics of the scene -Conditions of the scene -Environmental Conditions -Factors Pertinent to Entry and Exit -Scene Documentation -Search for Latent Prints -Additional Examinations

Orientation Issues

-Involve creating photographs where the viewer is lost in the scene or has no orientation. -Photographs are taken of an object with no scene reference. -Photographs are taken in which orientation is not clear.

Confusion Issues

-Involve creating photographs where the viewer is unclear of which item is being photographed or which photo came first. -Photographs show the scene in altered states. -Photographs show multiple similar items with no way to distinguish one from the other. This is particularly true when photographing small objects like shell casings and bloodstains.

ALS (Alternate Light Source)

-Involves light energy including and beyond normal visible light -Allows better visualization of different forms of evidence by combining various light wavelengths and barrier filters.

Controlling Focus and Depth of Field (focus/deptth of field)

-Is a function of the photographer, know what kind of focusing ring you have and practice with it. -In "smart" cameras you may have to turn off auto-focus features to get the proper ________ point. -Understand how to use the f-stop to create appropriate ____________. In overall and evidence establishing photos, good ______________ is a must.

Video Photography

-Is a functional supplement to crime scene documentation, but does not replace any documentation product.

Grid Search

-Is another variation on the strip search -Searches follows strips in one direction, then cuts across the scene in another set of strips, oriented 90 degrees to the first -Provides for multiple views of the same ground by the same searcher from different perspectives.

Crime Scene Sketching and Mapping -can sketch without mapping, but rarely does one map without sketching

-Is the act of drawing a 2 dimensional view of the scene and important artifacts -Is the process of measuring and recording the associated locations of these elements in the scene. -Important to place evidence in the crime scene, to interpret what happened -To understand what is going on, intorieation.

Quality photographs require that the investigator:

-Know their equipment and be practiced in it's use -Understand basic camera control.

In complex scenes, issues of size or resources may require the organization to alter its approach.

-Lack of equipment resources to handle multiple scenes, may force a functional approach. -If equipment resources are not an issue, but size is; area teams may be necessary to handle small zones within a larger scene. -The need for specialty examinations on scene may force a functional approach.

Measuring Light Energy

-Light is measured by it's wavelength -unit of measurement is a nanometer -nm=1/1,000,000,000 of a meter (1/1 billionth)

The crime scene report should not be used to:

-Make a cursory discussion of cenetral theme items in the scene and no other details -Make a rambling discourse of "why" the suspect is guilty or why he had to commit the crime. -Make a one-sided description of evidence that supports a single hypothesis.

How tight or how broad this search swathe will be is a product of several considerations:

-Nature of the ground being searched -Lighting Considerations -On-scene environmental conditions -Size of the item being searched for

Clean White Light (Clean/White Light)

-Necessary for basic observation -_______ designates ___________ that is similar to sunlight (5700 degrees Kelvin) -Allows visible colors to be visualized and photographed effectively and naturally.

Infrared Light

-Not particular new-corner to forensic work. ________ photography was a common surveillance tool used in the 1940-1950's -Not perceived by the human eye -Absorbed and reflected in such a fashion by various substances that it represents an important forensic tool.

Point to Point Search

-Not widely used in the US -Searches move from one focal point to the next, creating cleared pathways to and from each. -They do not stray from these pathways -Each focal point is dealt with before moving on to the next.

There are 4 key elements in crime scene documentation, they are:

-Notes -Photos -Sketches -Reports

Incomplete Documentation Issues

-Occurs when the crime scene team fails to capture pertinent scene details: -Too few photographs are exposed -Critical areas of the scene are forgotten -Methodical scene processing techniques help to eliminate this issue....

Evidence Collection teams require two indiividuals:

-One containnerizes and physically collects the items. =A second maintains the evidence log

Light

-One of the basic forms of energy, often called radiant energy or the electro-magnetic spectrum. -Simply a portion of the spectrum that the human eye can see.

Photography teams require 2 individuals:

-One operates the camera -Second maintains the photo log and assists

3 Basic types of photographs used to document every scene. These are:

-Overall photographs -Evidence establishing photographs -Evidence close-up phtographs

Identification issues involve creating photographs where the viewer is lost in the scene.

-Photographs are taken of items and the photo fails to illustrate what it is in the picture. -Or the photo documentation fails to illustrate why the photograph was taken in the first place.

Understanding basic camera control includes:

-Physical control of the camera -Light -Focus and Depth of Field

Good-quality photographs for crime scene work requires:

-Physical control of the camera -Proper use of the camera's controls such as aperture, shutter speed and lens -Proper composition

Investigative Notes

-Prepared to create a contemporaneous record of the action taken in the crime scene -Support photographs and sketches and will be the basis of any subsequent report. -Include positive actions taken and those where efforts fail, detailing negative eividence.

Common Forms of ALS

-RUVIS (Reflected Ultra-violet Imaging -UV (Ultra Violet) -IR (Infrared) -Broadband Blue Light

The title block of the sketch typically includes 5 items:

-Report Number -Physical Address of the scene -Name of the Sketch Creator -Time when sketch was created -Date when the sketch was created

Crime Scene Photography

-Seeks to establish a visual record of the condition of the scene and the items present in it. -This record should lead the viewer from the overall perspective to the details of specific objects. -Although simple in concept, there are recurring problems associated to ____________.

Size of item being sought

-Sometimes we do directed searches, looking for a specific object, which impacts our decisions. -It is one thing to look for a gun in the grass, it's another to look for a shell casing

There are problems encountered in crime scene video, requiring certain precautions:

-Turn off audio unless intending to narrate -Don't move, pan or zoom the camera too quickly as this re'sult in abrupt motion and bad focus. -Unless in sunlight always use a video strobe, never use a flashlight to illuminate the scene.

Zone Search

-Used in several variations -To deal with small confined spaces where no patterned search will work. -To break a larger scene up into functional areas, that are then searched using some other patterned technique. -No pattern search will work, so ________ are created that are searched individually.

Line Search

-Variation of the strip search, where multiple searchers follow a single strip in one direction, while on-line with each other. -Excellent for exterior scenes over rough terrain. -Usually requires supervisors to maintain the direction and alignment of the involved searches.

ALS Application

-Will help visualize: -Fluids and biological matter -Fibers and some hairs -Bruises or bite marks -Enhancing and visualizing bloodstains or GSR -Alterations to documents

3-Dimensional "Sketches"

-With the on-set of technology, detailed measurements from the scene can be used to create "virtual" scenes -This allows a _______________ perspectives from any position in the scene. -This also allows the creation of "walk through" demonstrative evidence that shows the jury the scene.

X-Ray Energy (Medical Imaging)

1-200nm

Typical Barrier Filter Operation

1. Excitation Filter 2. Light Strikes Substance 3. Release of Energy 4. Barrier Filter

Personal Protective Equipment

1. Goggles/Eye Protection 2. Face/Particle Mask 3. Tyvek Suit 4. Rubber Gloves 5. Booties

When light energy encounters an object, it can act on the object in 4 basic ways:

1.) Energy will be reflected 2.). Energy will be absorbed 3.). Energy will be transmitted 4.). Energy will be converted

There are 5 essential elements included on a crime scene sketch:

1.) Heading 2.) Diagram Area 3.) Legend 4.).Title Block 5.) Scale and Direction Notations

All narrative descriptions share 3 general attributes:

1.) Narrative is detailed. 2.) Narrative is accurate. 3.) Narrative is understandable

There are 6 common mapping methods. Name them:

1.) Rectangular Coordinates 2.) Triangulation 3.). Baseline Coordinates 4.). Triangulation or Rectangular Coordinates 5.). Triangulation on a Baseline

Short-Wave UV

100-280nm

Heat Energy

2,000-12,000nm

UV Energy (Woods Lamp)

200-400nm

Long-Wave UV

315-400nm

Visible Light

400nm (violet) - 700nm (red)

Assessing, Observing, Documenting, Searching, Collecting, Analyzing

6 Crime Scene Activities

Infrared Energy

700-2000nm

Scene Documentation

A description of efforts taken by the crime scene investigator to document the condition of the scene.

Factors Pertinent to Entry and Exit (Entry)

A description of the condition of doors, windows or other _________ points. This may require some level of inference on the part of the investigator.

Characteristics of the Scene

A description of the general features of the scene such as the building or room layout, furniture, doors and windows, these are static and stable conditions.

Environmental Conditions

A description of the general weather conditions and any scene specific conditions noted

Conditions of The Scene

A description of the specific conditions and aspects of the scene as found and a detailed description of all items of evidence.

Peak to Peak

A light's wavelength (nm) is measured, how?

Nature of the ground being searched Lighting Conditions On-Scene Environmental Conditions Size of the item being searched for

A search of the scene will be required to locate any evidence that is present. Whatever swath that a single searcher is responsible for at any moment. The swath size (width of the area the searcher is viewing) is. affected by the following factors:

Heading

A simple title that explains the purpose of the sketch

A supplemental purpose of photographs is to illustrate the scene condition to the court. For a photograph to be admissible in court, it will likely have to withstand several tests, which will be answered with 3 questions. What are they?

A.). Does the photograph accurately depict the scene? B.) Is the photograph generally free of distortion? C.). Is the photograph material and relevant to some aspect of the case at hand?

Name sections or descriptions of additional evaluations or examinations that might be included in the crime scene report:

A.). Evident fire patterns and fire-flow evaluations at fire scenes B.). Trajectory analysis in shooting scene C.). Bloodstain pattern analysis in violent scenes D.). Electro-Static Lifter examination for footwear E.). Specialized chemical enhancements

Without compromising the primary purpose of taking the photographs, the crime scene investigator can take certain steps to meet the legal requirements to be admissible in court. What are the 3 steps?

A.). Know how to use the camera, so the focus and lighting of the resulting photographs are the best they can be. B.). Do not overuse the wide-angle lens as it introduces distortion. C.). Choose the right lens for the right room

Title Block

Administrative data, indicating case number, address of the location, date and time the sketch was prepared by whom.

Who entered the scene? When they entered? What their purpose was? When they departed?

After defining the points of access on the perimeter, the crime scene team must decide how they will document access control using the crime scene entry-control log. The entry-control log is a simple document that identifies.

Narrative is Detailed

All pertinent details observed are documented.

Legend

Annotations that explain any symbols used in the sketch.

Scale and Direction Notation

Annotations that indicate the direction north as depicted by the sketch and whether any scale was used.

Initial Perimeter

Are often a single barrier, leaving little if any buffer between the crime scene and the on-lookers

455nm

At _______nm wavelength, biological fluids are easily observed in combination with an orange filter.

Lighting

Available ________ has a significant affect on the size of a search swathe

Avenues of Approach

Available: There may only be one point of acces Look for others

Perimeter

Based on experience they may recognize minor nuances that require expanding the __________

The 2 approaches for creating crime scene teams

By Area and By Function

Entry Control Logs

Can certainly be used at any perimeter, but they become a hindrance to operations.

Name the 5 basic search patterns for conducting a detailed crime scene search:

Circle or Spiral Search Strip and Line Search Grid Search Zone Search Point-to-Point Search

-Total Station -3D Laser Scanning Methods

Computer technology has contributed to the development of digital mapping methods. What are the 2 major digital mapping methods applicable to crime scenes?

Spectrum

Consists of everything from gamma radiation through radio and microwave

Excitation Filter

Creates specific wavelength of light

A.). Overall Photographs B.) Evidence Establishing Photographs C.). Evidence Close-Up/Forensic Quality Photographs

Crime scene photographs are used to support and enhance an understanding of the crime scene and the investigative report. There are 3 basic types of crime scene photographs. What are they?

Access the Scene

Determining how to ____________ isn't always difficult, but it isn't always simple either.

Single Barrier Perimeter

Does not provide a sufficient buffer for long-term scene effort.

Standard Crime Scene Sketch

Drawn as a 2-dimensional "bird's eye view, thus items on horizontal surfaces are easily indicated.

Pattern

Each _________ works in a variety of circumstances, but no single _______ works in every situation.

Single Barrier

Fine for the initial perimeter

Terrain

Has a significant affect on the size of a search swathe

400nm (Violet) & 700nm (Red)

Humans can visualize the radiant-energy spectrum, visualizing color from _______nm through ______nm wavelengths

Report Format: Introduction

Identify who is conducting the examination, the time and date and the specific location being examined.

Collection of Evidence

If a separate evidence log is created this is a synopsized discussion of major items of interest. It details the items recovered from the scene.

-Detailed, with all pertinent facts and conditions documented. -Accurate, with few inferences or subjective evaluations included. -Understandable; logical and organized.

If the crime scene technician is to accurately document the condition of the scene in as pristine a condition as possible, it is imperative that narrative scene descriptions be

Rubber Gloves

Impervious to liquid contamination

Tyvek Suit

Impervious to liquid contamination

Multi-level Containment, 2

In ____________, ___________ provide for 3 areas of access. This keeps support police out of the actual scene and others at a safe distance.

Normal Scenes

In ____________, custom and size of the organization will often determine the approach.

Size of the search swathe

In focused searches the size of the item being sought can affect ____________?

Crime Scene Notes

Include detailed narrative descriptions of observations and actions taken by the crime-scene investigator.

Scene

Investigators should re-access the ______ boundary after debriefing.

Multi-Level Containment

Involves 2 barriers which creates 3 areas of access: inner scene, working area, outer area.

Search Swathe

Is the area that any given searcher is viewing at any given moment in the search

Clean White Light

Is the most important too the crime scene technician uses in any crime scene

Crime Scene Mapping

Is the process of measuring and recording the actual location of evidence.

Light

Measured by it's wavelength

2

Multilevel containment of the scene is accomplished by using a minimum of how many perimeters?

Assessment

Must be accomplished before taking any action, but assessment is an on-going activity as well.

Search Pattern

No matter what ______________ is chosen, the crime scene team must decide on a search swathe size.

Narrative is understandable

Often reading the document must be able to make sense of it. -have someone critique -do so objectively

Biohazards from blood and other body fluids Structural hazards found in fire and explosion scenes Chemical and inhalation hazards associated with terrorism

Once a search method and approach are defined, the crime scene team must consider safety issues. Biohazards are clearly important, but the nature of hazards at the crime scene is not limited to biohazards. The full scope of hazards includes:

Scene.

Once the crime scene team is confident of the _________________, the team should act to further isolate the crime scene

Access to the Scene

Once the perimeter is established, a decision must be made on how the team will manage _______________.

They use the same criteria as the initial officer:

Primary Focal Points Avenues of entry or exit Secondary scenes

RUVIS

Reflected Ultra-Violet Imaging Systems

A.) Physical Control B.) Light C.) Focus and Depth of Field

Regarding camera control, what are the 3 basic aspects of the camera the crime scene investigator must be able to control in order to produce quality photographs?

Five Issues involved in Assessment

Scope and complexity of the scene, scene integrity and contamination control, team approach and composition, search methods to be used and personal protective measures.

The purpose of the debriefing and assessment by the CSI team is to consider 5 main issues. What are they?

Scope of the Scene Scene Integrity and Contamination Control Team Approach and Composition Search Methods to be used Personal Protective Measures

By Area

Single group of investigators is responsible for all activity in the scene.

Light Strikes Substance

Some energy is absorbed, exciting electrons in the substance. Some energy is reflected.

By Function

Specific groups are formed to handle different scene processing aspects (photo team, sketch team or latent team)

Booties

Splash and contact protection for footwear

Goggles/Eye Protection

Splash and mucous membrane tissue protection

Crime Scene Report

Synopsized version of these crime scene notes

False

T/F Once the final report is written, the investigator's notes become redundant and unnecessary; therefore, they can be disposed of?

False

T/F The departmental Public Information Officer (PIO) should be a rookie police officer, in order to give them the most exposure to media techniques and develop the skills necessary to "speak to the camera".

T

T/F: The crime scene notes should document all investigative efforts on scene, even when a technique employed on scene achieves negative results.

True

T/F: The crime scene report consolidates and synopsizes the relevant details from the crime scene investigator's notes

True

T/F: The purpose of a crime scene photograph is to accurately depict the scene without introducing distortion or visual bias...

True

T/F: UV eye protection is necessary when employing any UV light source.

Diagram Area

The actual sketch or drawing itself,

Single or Multiple Scenes Order of Activity involving speciality examination needs Available resources (equipment or personnel) Physical size of the scene

The composition of the crime scene team is first defined by whether the team's approach is one of area or function. Some factors to consider before making a determination of area vs. function include:

Release of Energy

The excited electrons fall back to normal energy state, releasing energy as light. This release is at a lower energy state than the original light.

Shorter

The higher the level of energy, the _________ the wavelength

Assessing

The investigator is constantly __________ the scene throughout processing.

Triangulation

The most effective method of fixing evidence in a crime scene is:

A.). Introduction B.). Characteristics of the Scene C.). Conditions of the Scene D.). Environmental Conditions E.). Factors pertinent to entry and exit F.) Scene Documentation G.). Collection of Physical Evidence H.) Search for Latent Prints I.). Additional Examinations

The most effective way of pulling salient facts from the crime scene investigator's notes is to organize the crime scene report into sections that deal with specific issues. Gardner and Krouskup suggest the following sections for the crime scene report:

Narrative is accurate

The narrative functionally matches the true description

Team on the western sid

The observations may not always be accurate, but they give the _______ a point to start from

Search Pattern

The particular ____________ chosen is a function of the situation

Greater

The shorter the wavelength, the _________ the ability to penetrate objects.

Bird's Eye

The vast majority of crime scene sketches are produced in which view?

1.) Cross-Projection Sketch 2.). Bird's Eye Sketch 3.) Elevation Sketch 4.). 3-Dimensional Sketch

There are 4 types of crime scene sketches. They illustrate different views to include horizontal surfaces, vertical surfaces, as well as combinations of these. What are the names of the 4 types of crime scene sketches. 1.) Cross-Projection Sketch 2.). Bird's Eye Sketch 3.) Elevation Sketch 4.). 3-Dimensional Sketch

A.) Identification Problems B.) Orientation Problems C.) Incomplete Documentation

There are a number of problems encountered in crime scene photography. It is possible for the crime scene investigator to take photographs at the crime scene that create significant comprehension problems for the viewer. Those comprehension problems include:

Outer Area

This i everything, on the outside of the second barrier, where on-lookers, media and others may gather

Access Points

This involves identifying actual ______________ for the team and establishing entry control points.

Working Area

This is an area surrounding the inner scene, where other support police may enter, equipment is staged and evidence is brought in.

Inner Scene

This is the actual crime scene, where only authorized investigators and crime scene technicians operate

Search for Latent Prints

This section describes all on-scene fingerprint recovery techniques

Additional Examination

This section describes other examinations such as bloodstain patterns, trajectory analysis, impression casting, etc. Each area can be broken down into subsection as required.

-Cross Projection Sketch -Elevation Sketch

Two additional views allow the crime scene investigator to show additional details associated to vertical surfaces, these are:

Crime Scene Reports (report)

Ultimately the actions and critical observations made by the crime scene investigator must be __________. -The investigative notes serve as the basis of this _______, but must be condensed. -Is prepared as a stand-alone document, organized and understandable.

Search

Ultimately, some form of __________ must be conducted at the scene to locate evidence

Nanometer

Unit of measurement for Light

Scene Scope and Nature Changes to the Scene Status of Involved Parties Scene Security

Upon arrival at the scene, the crime scene team must seek out the initial responding officer. Once found, this individual should be interviewed to determine the following:

Entry Control Log

Used for the inner perimeter, keeps track of who entered the scene, when, and why they left. Serves to validate scene integrity.

-Ease of use -Mobility -Accuracy

What are the 3 primary considerations (besides cost) relative to the decision to purchase a 3-D scanning system?

Determining how to access the scene is a function of 3 factors:

What avenues of approach are available? Will these points expose operations to media scrutiny? What avenues of approach or exit did the offender use?

Crime Scene Photo Log

What can the crime scene investigator use to keep track of each photograph taken at the scene? This item includes basic administrative data, the exposure number, what the photograph depicts, and any remarks.

Debriefing of initial responders seeks to answer:

What is the scope and nature of the scene? What actions or alterations have been taken or noted by first responders (including EMS)? What is the status of involved parties? What level of security has been established and what further security has been established and what further security actions are required?

Tripod

What stabilizing device can be used to physically control the camera in order to ensure a sharp focus and produce better documentation, especially with close-up photographs?

5

When using triangulation as a mapping method, how many measurements are necessary to fix a regularly shaped object, such as a gun, in the crime scene sketch?

2

When using triangulation as a mapping method, how many measurements are necessary to fix an irregularly shaped object, such as a pool of blood or a pile of clothes, in the crime scene sketch?

3 Factors

With these ______________ in mind the crime scene team decides what points they will use to access the scene for processing purposes.

Assessment

________ by the crime scene team always involves a debriefing of the initial responders.

Blood/GSR

____________ & __________ both absorb effectively in the IR spectrum causing them to appear darker. Many dyes associated with cloth and fabric may reflect the IR causing them to appear lighter.


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