Unit 8 Preserving the Crime Scene Using crime scene drawings for creating demonstrative evidence

Evidence and the Crime Scene A criminal investigation must be concerned with both people and things. A criminal investigation must be concerned with both people and things. By using human testimony and physical evidence, a prosecuting attorney can more accurately prosecute a case against a defendant and engage a jury. By using human testimony and physical evidence, a prosecuting attorney can more accurately prosecute a case against a defendant and engage a jury.

Evidence and the Crime Scene Evidence: Any item that helps to establish the facts of a related criminal case. It may be found at the scene of the crime or on the victim or taken from the suspect or the suspect’s environment.

Evidence and the Crime Scene What exactly is forensic science? Forensic science Forensic science The application of science to law, and the use of science and technology to determine the value of evidence. The application of science to law, and the use of science and technology to determine the value of evidence. Criminalist (or forensic specialist) Criminalist (or forensic specialist) A person specifically trained to collect evidence and to make scientific tests and assessments of various types of physical evidence. A person specifically trained to collect evidence and to make scientific tests and assessments of various types of physical evidence.

Evidence and the Crime Scene In some jurisdictions investigators can call on these trained technicians to aid in the search for evidence, and they are often referred to as crime scene investigators (CSI). In some jurisdictions investigators can call on these trained technicians to aid in the search for evidence, and they are often referred to as crime scene investigators (CSI).

The Crime Scene Sketch Accurately portrays the physical facts Accurately portrays the physical facts Relates the sequence of events at the scene Relates the sequence of events at the scene Establishes the precise location and relationship of objects and evidence at the scene Establishes the precise location and relationship of objects and evidence at the scene Creates a mental picture of the scene for those not present Creates a mental picture of the scene for those not present Is a permanent record of the scene Is a permanent record of the scene

Evidence and the Crime Scene Eight basic procedures during the crime scene investigation to gather and preserve evidence: Eight basic procedures during the crime scene investigation to gather and preserve evidence: Recognize or discover relevant physical evidence. Recognize or discover relevant physical evidence. Examine evidence to determine that it can be tested or compared in a crime laboratory. Examine evidence to determine that it can be tested or compared in a crime laboratory.

Evidence and the Crime Scene Collect evidence with care and diligence, according to standard procedures, and in a lawful manner. Collect evidence with care and diligence, according to standard procedures, and in a lawful manner. Carefully handle, package, and label evidence to avoid damage, loss, contamination, or questionable links in the chain of custody. Carefully handle, package, and label evidence to avoid damage, loss, contamination, or questionable links in the chain of custody.

Evidence and the Crime Scene Prioritize Collection of Evidence. Prioritize Collection of Evidence. Consider collection based on the evidence. Latent prints, biological fluids, trace evidence. Consider collection based on the evidence. Latent prints, biological fluids, trace evidence. Consider environmental conditions into your process. Rain/wet vs. dry/hot Consider environmental conditions into your process. Rain/wet vs. dry/hot

Crime Scene Sketch Assistance 1) Interviewing and interrogating persons 2) Preparing an investigative report 3) Presenting the case in court The sketch supplements photographs, notes, plaster casts and other investigative techniques. The sketch supplements photographs, notes, plaster casts and other investigative techniques.

Two Types of Sketches Rough sketch Rough sketch Finished or scale sketch Finished or scale sketch

The Rough Sketch The rough sketch is the first pencil-drawn outline of the scene and the location of objects and evidence within this outline. The rough sketch is the first pencil-drawn outline of the scene and the location of objects and evidence within this outline. Usually not drawn to scale Usually not drawn to scale Although distances are measured and indicated in the sketch Although distances are measured and indicated in the sketch Sketch after photographs are taken and before anything is moved. Sketch after photographs are taken and before anything is moved.

The Rough Sketch Sketch as much as possible Sketch as much as possible Nearby streets Nearby streets Vegetation Vegetation Paths of entrance and exit Paths of entrance and exit

Sketching Materials Use graph paper Use graph paper If not a skilled “artist type” Paper Paper Pencil Pencil Measuring tape Measuring tape Ruler Ruler Straightedge Straightedge Clipboard Clipboard Eraser Eraser Compass Compass Protractor Protractor Thumbtacks Thumbtacks

Sketching Strategies Observe and plan Observe and plan Measure distances Measure distances Outline the area Outline the area Locate objects and evidence within the outline Locate objects and evidence within the outline Record details Record details Make notes Make notes Identify the sketch with a legend and a scale Identify the sketch with a legend and a scale

Observe & Plan What is relevant to the crime being investigated? What is relevant to the crime being investigated? Where the crime took place determines how many sketches you will do. Where the crime took place determines how many sketches you will do. Decide where to start Decide where to start Clockwise Clockwise Counterclockwise Counterclockwise One end or the other One end or the other

Evidence and the Crime Scene Carefully record how, where, and by whom evidence was located to ensure that evidence has not been tampered with or altered. Carefully record how, where, and by whom evidence was located to ensure that evidence has not been tampered with or altered. Carefully transport evidence to a laboratory, maintaining the proper chain of custody and security. Carefully transport evidence to a laboratory, maintaining the proper chain of custody and security.

Evidence and the Crime Scene Focus on the easily accessible areas in plain view and work towards out-of-view areas. Focus on the easily accessible areas in plain view and work towards out-of-view areas. Maintaining your systematic search patterns. Maintaining your systematic search patterns. Collect evidence by using a process that does not compromise other evidence. Collect evidence by using a process that does not compromise other evidence.

Evidence and the Crime Scene Concentrate on the most transient evidence and work to the least transient forms of physical evidence. Concentrate on the most transient evidence and work to the least transient forms of physical evidence. Remember, the environment can change and affect evidence. Remember, the environment can change and affect evidence.

Evidence and the Crime Scene Maintain the integrity of the chain of custody from the crime lab to the court after tests have been completed. Maintain the integrity of the chain of custody from the crime lab to the court after tests have been completed. Present or explain evidence in a court proceeding, substantiate the find if necessary, and document the chain of custody. Present or explain evidence in a court proceeding, substantiate the find if necessary, and document the chain of custody.

Evidence and the Crime Scene The ultimate success or failure of a criminal investigation depends on: The ultimate success or failure of a criminal investigation depends on: Thoroughness exercised at the crime scene Thoroughness exercised at the crime scene Preserving Preserving Collecting Collecting Recording all available information Recording all available information

Evidence and the Crime Scene

Pictorial Documentation of the Crime Scene Photographs of the scene of a serious criminal act should be taken as soon as possible after preliminary investigation priorities have been taken care of, before note taking, sketching, or the search of additional evidence begins. Photographs of the scene of a serious criminal act should be taken as soon as possible after preliminary investigation priorities have been taken care of, before note taking, sketching, or the search of additional evidence begins.

Photographing the Crime Scene The role of photographs in a criminal investigation is to present a logical story visually. The role of photographs in a criminal investigation is to present a logical story visually. Nothing in the crime scene should be disturbed before photographs are taken. Nothing in the crime scene should be disturbed before photographs are taken. When photographing a crime scene, follow the axiom “More is better.” When photographing a crime scene, follow the axiom “More is better.”

Camera Choices 35 mm Both black and white and colored film may be used at the crime scene. Both black and white and colored film may be used at the crime scene. High-speed films are especially useful for capturing pictures even in low-light conditions. High-speed films are especially useful for capturing pictures even in low-light conditions.

Camera Choices Traditionally, a single lens reflex (SLR) camera has been selected to photograph crime scenes. Traditionally, a single lens reflex (SLR) camera has been selected to photograph crime scenes. The SLR camera typically is compact and comes in a variety of formats, from manually focusing units to fully automatic units complete with automatic focusing, flash, and winding. The SLR camera typically is compact and comes in a variety of formats, from manually focusing units to fully automatic units complete with automatic focusing, flash, and winding.

Camera Choices Digital Digital cameras have a number of advantages when used in crime scene photography: Digital cameras have a number of advantages when used in crime scene photography: They require no chemical processing They require no chemical processing Can be displayed on the camera immediately Can be displayed on the camera immediately Can be transferred to a computer and stored in an electronic database Can be transferred to a computer and stored in an electronic database Are now accepted in most courts Are now accepted in most courts

Camera Choices Megapixels Refers to picture image resolution. Refers to picture image resolution. A mega equals 1 million. A mega equals 1 million. Pixels are the smallest unit of brightness and color. Pixels are the smallest unit of brightness and color. More pixels mean sharper, clearer, and better images. More pixels mean sharper, clearer, and better images.

Camera Choices Video Good briefing tool for police officers who have not visited the crime scene. Good briefing tool for police officers who have not visited the crime scene. Can be an additional aid for the prosecutor in presenting a criminal case. Can be an additional aid for the prosecutor in presenting a criminal case. They are not a substitute, however, for either photographs or sketches of the crime scene. They are not a substitute, however, for either photographs or sketches of the crime scene.

Photo Organization Progress from the general to the specific. Progress from the general to the specific. long-range long-range mid-range mid-range close-up close-up Sometimes it may be necessary to include a measurement scale in photographs of objects at a crime scene. Sometimes it may be necessary to include a measurement scale in photographs of objects at a crime scene.

Photo Organization The first photograph on every roll of film shot at the crime scene should be a title card indicating: The first photograph on every roll of film shot at the crime scene should be a title card indicating: Crime location Crime location Date Date Case identifier Case identifier Photographer Photographer Roll number Roll number

Photo Organization River City Police Department River City Police Department September 4, 2008 September 4, Unlucky Drive – Living room 1312 Unlucky Drive – Living room River City CA River City CA RC RC Officer Widelens Officer Widelens Roll one of three Roll one of three

Sketching the Crime Scene Sketches are useful in questioning witnesses and suspects and when writing investigative reports. Sketches are useful in questioning witnesses and suspects and when writing investigative reports. Sketches offer accurate information about the placement of objects. Sketches offer accurate information about the placement of objects. Sketches show relationships and distances between things. Sketches show relationships and distances between things.

Sketching the Crime Scene For a sketch or diagram to be legally admissible in court, it must meet the following requirements: For a sketch or diagram to be legally admissible in court, it must meet the following requirements: It must be part of a qualified person’s testimony. It must be part of a qualified person’s testimony. It must recall the situation that the preparer saw. It must recall the situation that the preparer saw. It must express the place or scene correctly. It must express the place or scene correctly.

Preparing the Sketch A crime scene sketch complements the notes and photographs taken during the crime scene investigation. A crime scene sketch complements the notes and photographs taken during the crime scene investigation.

Measure & Outline the Scene A steel tape is best because it does not stretch A steel tape is best because it does not stretch Use conventional units of measurement Use conventional units of measurement Inches Inches Feet Feet Centimeters Centimeters Meters Meters Have both officers look at the actual measurements Have both officers look at the actual measurements This eliminates hearsay evidence This eliminates hearsay evidence

Preparing the Sketch Try to use the largest scale possible. All sketches should include: – A compass or an orienting compass arrow indicating north. – A legend or key to explain letters, numbers, or symbols used. – An indication of the scale used.

Measuring North should be at the top of the paper. North should be at the top of the paper. Determine Scale Determine Scale Take the longest measurement at the scene and divide it by the longest measurement of the paper used for sketching. Take the longest measurement at the scene and divide it by the longest measurement of the paper used for sketching. ½” = 1’ small rooms ½” = 1’ small rooms ¼” = 1’ large rooms ¼” = 1’ large rooms 1/8” = 1’ very large rooms 1/8” = 1’ very large rooms ½” = 10’ large buildings ½” = 10’ large buildings 1/8” = 10’ large land area 1/8” = 10’ large land area

Sketching Methods Rectangular-coordinates method A sketching method that involves measuring the distance of an object from two fixed lines at right angles to each other. A sketching method that involves measuring the distance of an object from two fixed lines at right angles to each other. It is often used to locate an object in a room. It is often used to locate an object in a room.

Measuring Measure from fixed locations Measure from fixed locations Walls Walls Trees Trees Telephone poles Telephone poles Building corners Building corners Curbs Curbs

Sketching Methods Triangulation method A sketching method that requires measuring the distance of an object along a straight line from two widely separated, fixed reference points. A sketching method that requires measuring the distance of an object along a straight line from two widely separated, fixed reference points.

Sketching Methods Baseline method Baseline method A sketching method that takes measurements along and from a single reference line, called a baseline, which can be established by using a length of string, a chalk line, or some convenient means. A sketching method that takes measurements along and from a single reference line, called a baseline, which can be established by using a length of string, a chalk line, or some convenient means.

Sketching Methods Compass point method Compass point method A sketching method that requires a protractor or some method of measuring angles between two lines. A sketching method that requires a protractor or some method of measuring angles between two lines. One point is selected as the origin and a line extended. One point is selected as the origin and a line extended.

Sketching Methods Cross projection method Cross projection method A sketching method in which the ceiling appears to open up like the lid of a hinged box, with the four walls opening outward A sketching method in which the ceiling appears to open up like the lid of a hinged box, with the four walls opening outward Measurements are then indicated from a point on the floor to the wall. Measurements are then indicated from a point on the floor to the wall.

Take Notes After completing the sketch, make notes of lighting condition, weather, colors, people present at the scene, and all relevant information. After completing the sketch, make notes of lighting condition, weather, colors, people present at the scene, and all relevant information.

Create a Legend/Table Contains: Contains: Case number Case number Type of crime Type of crime Name of victim or defendant (if known) Name of victim or defendant (if known) Investigator Investigator Persons assisting Persons assisting Direction of North Direction of North Identifying information in sketch Identifying information in sketch

Equipment for Sketches A supply of pencils (medium or hard lead) A supply of pencils (medium or hard lead) Graph paper and blank paper Graph paper and blank paper A clipboard or other solid portable drawing surface A clipboard or other solid portable drawing surface A metal tape measure of at least 50 feet A metal tape measure of at least 50 feet A folding ruler, such as the standard 6-foot folding ruler used by carpenters, for short measurements A folding ruler, such as the standard 6-foot folding ruler used by carpenters, for short measurements

Equipment for Sketches A 12- or 15-inch ruler for drawing straight lines, drawing to scale, or making very short measurements A 12- or 15-inch ruler for drawing straight lines, drawing to scale, or making very short measurements A reliable compass or some other means of finding north A reliable compass or some other means of finding north A protractor for drawing and measuring angles A protractor for drawing and measuring angles

Equipment for Searches Latex gloves Compass Latex gloves Compass Camera, film String Camera, film String Rope Knife Rope Knife Evidence tags Steel tape measure Evidence tags Steel tape measure Assorted containers Ruler Assorted containers Ruler Assorted envelopes Pens Assorted envelopes Pens Pill boxes Indelible marker Pill boxes Indelible marker Magnifier Paper Magnifier Paper Test tubes Fingerprint kit Test tubes Fingerprint kit Plastic bags Shovel Plastic bags Shovel Bottles Flashlight, batteries Bottles Flashlight, batteries Cellophane tape Probing rod Cellophane tape Probing rod Ax Wire Ax Wire Saw First-aid kit Saw First-aid kit Wrecking bar Metal detector Wrecking bar Metal detector Chalk, chalk line Chalk, chalk line

Discovering and Recognizing Evidence After the crime scene has been photographed and sketched, you can begin a search. After the crime scene has been photographed and sketched, you can begin a search.

Admissibility as Evidence Demonstrative evidence is permissible to clarify opening and closing statements and may simplify testimonial evidence to focus on scene particulars. The issue becomes whether the evidence is admissible or is merely explanatory of the testimony and photographic/video evidence. Demonstrative evidence is permissible to clarify opening and closing statements and may simplify testimonial evidence to focus on scene particulars. The issue becomes whether the evidence is admissible or is merely explanatory of the testimony and photographic/video evidence. Drawn or personally witnessed by the investigator that accurately portrays the crime scene. Drawn or personally witnessed by the investigator that accurately portrays the crime scene.

Search Patterns Spiral search pattern Spiral search pattern A search pattern typically used in outdoor areas and normally launched by a single person. A search pattern typically used in outdoor areas and normally launched by a single person. He or she begins at the outermost corner and walks in a decreasing spiral toward a central point. He or she begins at the outermost corner and walks in a decreasing spiral toward a central point.

A 10’ 8’ Triangulation Method of Locating Evidence Item A is 10’ from the SE corner of the room, and 8’ from the SW corner of the room. These measurements will ALWAYS intersect at item A’s location.

A Triangulation Method of Locating Evidence First, the desk is not fixed, as it is not touching the wall and its location has not been determined. To fix the desk, do this: desk

A Triangulation Method of Locating Evidence Now that the desk has been fixed, object A can be fixed from two fixed points from the desk, as such: desk 3’ 1”

A Triangulation Method of Locating Evidence Now that the desk has been fixed, object A can be fixed from two fixed points from the desk, as such: desk 3’ 1” 6’ 5’

A Triangulation Method of Locating Evidence In this scenario, the desk is flush against the wall. How would object A be triangulated? desk

A Triangulation Method of Locating Evidence The flush side of the desk is already fixed. One measurement is required to place the desk along the wall. Object A is then triangulated as usual. desk 3’ 5’ 6’

A Triangulation Method of Locating Evidence This desk is flush in the corner against both walls. How would object A be triangulated? desk

A Triangulation Method of Locating Evidence Since two sides of the desk are already fixed, object A is triangulated as usual. desk 6’ 5’

A Triangulation Method of Locating Evidence Once evidence is triangulated, it can become a fixed point to triangulate other items of evidence. In this case, object B. desk 6’ 5’ B 2’

Rectangular-Coordinate Method A B 15’ 10’ 6’

N E S W Body Tree Shed Compass 40° 340° Azimuth Method of Triangulation Reverse azimuth: 340°-180°=160° 160° Reverse azimuth: 40°+180°=220° 220°

Administrative Data LEGEND A. Victim B. Revolver C. Shell Casing D. Blood Stain LEGEND A. Victim B. Revolver C. Shell Casing D. Blood Stain North North TITLE Case: Location: Payson Hall, Room 111 Victim: State of Washington Occurred: June Drawn by: Detective Baum Verified by: Detective Smith TITLE Case: Location: Payson Hall, Room 111 Victim: State of Washington Occurred: June Drawn by: Detective Baum Verified by: Detective Smith Not to Scale/1/4”= 1’ Not to Scale/1/4”= 1’

Search Patterns Strip search pattern Strip search pattern A search pattern in which the space to be searched is divided into a series of lanes A search pattern in which the space to be searched is divided into a series of lanes One or more searchers proceed up and down the lane, continuing until the area has been completely searched. One or more searchers proceed up and down the lane, continuing until the area has been completely searched.

Search Patterns Grid search pattern Grid search pattern A search pattern that consists of two strip searches, the second perpendicular to the first A search pattern that consists of two strip searches, the second perpendicular to the first It allows the area to be viewed from two angles. It allows the area to be viewed from two angles.

Search Patterns Zone search pattern Zone search pattern A search pattern in which the area is divided into four quadrants, each of which is then examined with one of the other patterns. A search pattern in which the area is divided into four quadrants, each of which is then examined with one of the other patterns.

Search Patterns Pie (or wheel) search pattern Pie (or wheel) search pattern A search pattern in which the area is divided into pie-shaped sections, usually six in number. A search pattern in which the area is divided into pie-shaped sections, usually six in number. Each section is then searched, usually by a variation of the strip search. Each section is then searched, usually by a variation of the strip search.

Collecting and Marking Evidence The court will want answers to the following questions about evidence collected at the crime scene: The court will want answers to the following questions about evidence collected at the crime scene: Who found it? Who found it? What did it look like? What did it look like? When was it found? When was it found? Where was it found, and what is its relation to other objects at the scene? Where was it found, and what is its relation to other objects at the scene? Where was it held from its collection to its presentation in court? Where was it held from its collection to its presentation in court?

Collecting and Marking Evidence The investigator who finds the evidence should place his or her personal identifying mark on it. The investigator who finds the evidence should place his or her personal identifying mark on it. The mark should be permanent and capable of positive identification. The mark should be permanent and capable of positive identification. Evidence that cannot be physically marked-- such as bird shot or liquids--should be placed in an appropriate container. Evidence that cannot be physically marked-- such as bird shot or liquids--should be placed in an appropriate container.

Collecting and Marking Evidence This receptacle should then be sealed and identified with a label or property tag indicating: This receptacle should then be sealed and identified with a label or property tag indicating: the title of the case the title of the case the officer’s name or initials the officer’s name or initials the date the date the time the time the specific location where it was found the specific location where it was found

Collecting and Marking Evidence A fairly common evidence container in use today is a 9” x 12” manila envelope. A fairly common evidence container in use today is a 9” x 12” manila envelope. Standard of comparison Standard of comparison A model, measure, or object with which evidence is compared to determine whether both came from the same source. A model, measure, or object with which evidence is compared to determine whether both came from the same source.