Certify Death

b. Demonstrate proper procedures for checking vital signs of a victim and certifying death of a victim.

• Pulse rate and rhythm: Checking your pulse rate is counting the number of times your heart beats in a minute. Pulse checks can be taken at the wrist (radial pulse) or at the neck (carotid pulse). Do not use your thumb; instead use your index and middle fingers.

Explain and demonstrate the use of crime scene photography

a. Demonstrate proper crime scene photography1. Three methods of crime scene recording: Photography, sketches and notes. 2. The crime scene should not be altered unless there are injuries. 3. Objects must not be moved4. Photos must form an organized sequence and show all locations and objects. 5. Take photos of the body’s location, position. 6. Take close ups of injuries, weapons near the body. 7. Photo the surface under the body after the body has been removed. 8. More is better motto9. Digital cameras allow for enhancement & examination in fine detail.10. 3 types of vantage points: • Long range may include aerial view or the view from the entry way• Mid-range may include using different angles 8 to 10 feet from the victim• Close-up may include body and body parts, weapons, casings, blood patterns

usually taken within 5 feet or less from the victim.

Document photographs taken at the crime scene.

• A measuring device will show the actual size of all objects. Photos with measurement and without are necessary.

• The first shot should be a title card that includes the crime location, date, case number, photographer.

• All photos will be identified by a number and entered in the photo log.

EQ: How do investigators record and preserve a crime scene? 4

Photography: Purpose1. To record the original scene and related

areas 2. To record the initial appearance of physical

evidence 3. It will provide investigators and others with

this permanent visual record of the scene for later use

4. Photographs are also used in court trials and hearings

EQ: How do investigators record and preserve a crime scene? 5

Photography

• Scene must be unaltered except for medical assistance

• Completely photograph entire scene• Include all adjacent areas• Overview of the scene• Start at body and work to less significant

evidence

EQ: How do investigators record and preserve a crime scene? 6

Photography• Get injuries and all evidence on body• Take two photographs of each item of

evidence – One should be an orientation (midrange) shot to

show how the item is related to its surroundings – The second photograph should be a close-up to

bring out the details of the object itself • Use ruler on objects where size is important

for scale

Demonstrate standard procedures for searching for, collecting, removing and evaluating physical evidence from a crime scene

• Explain and demonstrate appropriate search method to use• Spiral-used in outdoors, begin in the outermost corner and walk in a

decreasing spiral towards a central point. Never do this in reverse order, because you will destroy evidence.

• Strip search pattern is used outdoors or in large indoor areas. Imagine a

series of lanes dividing up the entire space to be searched. The searchers move up and down each lane.

• Grid search pattern-begins like a strip search, however after completing

the horizontal lanes, the searchers double back at right angles to the original strip search. This is ore time consuming and more thorough.

• Zone search is when the investigator creates two imaginary axes, which

divide the area into four quadrants. Each quad can then be examined with one of the previous describe patterns.

EQ: How do investigators record and preserve a crime scene? 9

EQ: How do investigators record and preserve a crime scene? 10

Searching the Crime Scene

• Must be thorough, ALWAYS• Assign a supervisor to coordinate search

and oversee collection of evidence• Search is based upon nature of crime.• Final search is for trace evidence• Autopsy is also a search

Identify evidence at a crime scene:

• The officer must do a walk through and look for all types of evidence.

• The crime scene should be secured and protected against interference by unauthorized people

• Securing the crime scene may require covering suspected items with paper, boxes, or plastic to ensure they are not moved.

• Set up barricades, tape off the area, or station officers to guard against entry into the area.

• Photographing and sketching the crime scene should be done before physical evidence is collected.

• Search for latent fingerprints, casts of footprints tracks, and tool impressions

Document location where evidence was collected:

Explain methods for collecting DNA evidence

• A process where DNA is extracted from biological evidence samples collected at a crime scene and compared with samples taken from the victim and suspects.

• The DNA samples are analyzed and compared to determine whether they have a common origin.

• Hair found at the scene should be placed in a paper packet and then placed in an envelope.

Type of evidence that has DNA

• Blood and bloodstains• Semen and seminal stains• Tissues and cells• Bones and organs• Hairs with follicles• Urine and saliva (with nucleated cells)Other types of biological evidence, such as tears,

perspiration, serum and other body fluids without nucleated cells are not amenable to DNA analysis.

Evidence Examples

Images: http://www.state.nj.us/njsp/divorg/invest/criminalistics.html

Did you know? Most paint evidence submitted to a lab will come from hit-and-run cases involving automobiles.  

Paint

• Physical and chemical analysis of paint evidence (chips or residue) can indicate it’s class, such as automobile paint, house paint, nail polish, etc. The evidence can be compared to 40,000 different types of paint classified in a database, which can be used to identify a particular make or model of car or brand of tool.

• Paint evidence can also indicate individual characteristics if an investigator is able to find similarities between two samples, such as the color, number of layers, chemical composition, or a physical match between the edges of two paint chips – one from a tool and one from a crime scene.

Paint Layers Physical Match of Paint Chip Edges

Paint Transfer on a Car

Tiny Pieces of Evidence

Images: http://www.rsc.org/images/b606109e-300-(FOR-TRIDION)%20(iStockphotos)_tcm18-68354.jpg, http://www.mtcforensics.com/investigation.html

Glass

• Glass particles can be found at various crime scenes, such as breaking and entering, hit and run, vandalism, or murder. 

• Glass at a crime scene is analyzed to determine its color, surface characteristics, tint, thickness, density, chemical composition, and refractive index (RI).

• The results of the tests provide clues about the crime and help investigators connect the evidence to a suspect or other object used in a crime, such as matching glass from a crime scene to a headlight to a suspect’s car.

The pattern of cracks in a windshield fracture can reveal information about speed, occupant position, and angle of impact.

Magnified image of glass fragments

CSI Glass Analysis

Image: http://www.state.nj.us/njsp/divorg/invest/criminalistics.html

Explosives

• Explosive substances can be examined to determine its chemical composition to identify the type of explosive used and its origin.

• Traces of explosives found on a suspect’s clothing, skin, hair, or other objects may be matched to explosives from the crime scene.

• Materials used to make an explosive device will be compared to evidence found in the suspect’s possession to confirm a match.

CSI & Explosives

Image: http://www.geocities.com/j_ksinha/img/mid1.gif

Ballistics

• Characteristics of ammunition, firearms, and residue are examined to find matches between suspects and the evidence found at a crime scene.

• Chemical tests can reveal gunshot residue (GSR) on the hands, face, or clothing of a victim or suspect to indicate how close a person was to a fired gun.

• Rifling (grooves) in a gun barrel causes distinctive grooves, indentations and scratches upon fired bullets, which can be matched to the weapon that fired them.

• Police are able to search the Integrated Ballistics Identification System (IBIS) database to compare markings from bullets, cartridge cases, and shotgun shells to ballistic evidence.

Investigators can compare the striations on bullets to see if

they match.

Did you know? Caliber (handguns & rifles) or gauge (shotguns) refers to the size of the internal diameter of a gun’s barrel.

Learn more about ballistics …

Images: http://www.npsg.uwaterloo.ca/resources/images/microscope/Sand%200004.jpg

Dust & Dirt

• Dust, dirt, or sand evidence can reveal where a person has traveled and may be picked up at a crime scene or left behind.

• Investigators examine the samples for chemical composition, pollen, plant material, and other organic matter to find links to a specific crime scene.Microscopic Image of Sand

Fingerprints

• There are 3 types of fingerprint patterns: arches, loops, and whorls. Investigators also identify unique ridge characteristics in a fingerprint that can be used to identify a suspect or victim.

• AFIS (Automated Fingerprint Identification System) is a database used by investigators at local, state, and national levels to search for matches to fingerprints found at a crime scene.

Images: http://www.wrongfulconvictionlawsuitdefense.com/uploads/image/28santos_600.jpg, http://www.dps.state.ia.us/DCI/Crime_Lab/images/toolmarks.jpg, & http://www.masterpiecestudios.com/images/171463.gif

Impression Evidence

Shoeprints & Tire Tracks• Impression evidence can be photographed, lifted with tape, or cast with plaster to compare to a suspect’s shoes or tires. • Investigators will examine the evidence to identify the brand of shoe or tire based on its tread pattern and other physical features to provide leads in the case.• Shoes and tires will also show wear patterns after being used for a period of time as well as other features (scratches, nicks, and cuts) that can be used to match evidence to specific items. For example, shoeprints can be matched to a suspect based on how the treads on the shoes that are worn down due to that person’s walking style.

Bite Marks• Each of the 32 teeth in humans is unique due to age and wear.• Impressions and photographs of bite marks left on a victim, assailant, or other object at a crime scene can often be matched to dental records.

Tool Marks• Tiny nicks and chips form on the edges of a tool as it is used, which can be used to identify matches between evidence and suspects. • Tools may also pick up traces of blood or other substances that can be tested or have fingerprints that can be lifted.

Images: http://www.modernmicroscopy.com/main.asp?article=11&print=true&pix=true

Fracture Matches

• When an object broken, torn, or cut, two unique edges are formed, which are referred to as fracture lines.

• These edges can be compared by the naked eye or with microscopes to see if they fit together , which indicates that they may have been part of the same object at one time.

• Investigators may compare the edges on pieces of tape, glass fragments, paint chips, pieces of a car from an accident, paper bag, etc. to find possible matches.

Duct Tape Evidence

Image: (Bottom Left): http://dofs.gbi.georgia.gov/vgn/images/portal/cit_11783501/81672146questioned%20document.jpg

Questioned Documents

• Examiners will analyze a ransom note or other document to find clues to link it to a crime scene or a specific suspect. They will analyze the type of paper used, printing method or handwriting style, and type of ink.

• Other unique features, such as watermarks on stationary or indentations made as someone wrote on a page in a notebook, may provide useful clues.

Wounds

• Wounds can often be matched to weapons or tool marks on the weapon. Investigators may also be able to determine the weapon's size, shape, and length. 

• Analysis of a wound may provides clues to a victim’s injuries, characteristics of the suspect (left-handed, right-handed, height, etc.), and positions of the victim and suspect at the time of the incident.

FBI Questioned Documents

UNIT

Images: http://biology.arizona.edu/sciconn/lessons2/Vuturo/vuturo/photos/desmus.gif

DNA

• Investigators can extract DNA from almost any tissue, including hair, fingernails, bones, teeth and body fluids. The DNA is used to create a profile that can be compared to profiles from suspects or victims.

• CODIS (Combined DNA Index System) is a database maintained by the FBI that is used to find matches to unknown DNA samples from a crime scene.

Insects

• Flies, beetles, and other insects can provide useful clues about a corpse.

• Forensic entomologists use factors such as weather conditions, the location and condition of the body, and their knowledge of the life cycles of insects to help them estimate the postmortem interval or PMI (the time between death and the discovery of the body). 

Source: http://www.crime-scene-investigator.net/excavation.html Images: http://www.celticnz.org/images/Feedback/SkullSkeleton.JPG and http://www.legacyhealth.org/images/Housecalls/claviclefx.jpg

Skeletal Remains

• Forensic anthropologists analyze skeletal remains to determine four characteristics for a victim: age, sex, race, and stature (height/build).  Sex - Determined by examining the pelvis, humerus, and femur Age and stature – Determined by analyzing the development of the teeth, bone growth, and the length of specific bones, such as the femur. Race – Determined by analyzing the skull for characteristics that are common among people of different races.

• DNA samples can be collected from bone, teeth, and hair to provide clues to a person’s identity. Scientists may also be able to gain clues as to a person’s past, recent injuries, or the cause of death based on bone fractures and other signs of trauma.

Source: http://www.virtualsciencefair.org/2004/fren4j0/public_html/trace_evidence.htm Images: http://www.trutv.com/library/crime/criminal_mind/forensics/chinatown_widow/4.html

Examples: Vomit and urine can be used to test for alcohol, drugs, and poisons. Cigarette butts may contain dried saliva. Semen containing sperm is valuable for DNA analysis. Blood can provide DNA evidence and blood spatter can provide clues about the crime.

Body Fluids

• Blood, semen, saliva, sweat, and urine can be analyzed to give investigators information about the crime as well as its victim or the suspect.

• Chemicals and ultra violet light can be used at a crime scene to find body fluid evidence. Areas with potential evidence are swabbed, bagged and collected in vials, which are air tight and have a low risk of cross contamination.

Hairs & Fibers

• Hairs and fibers may be transferred from the suspect or the suspect’s clothes to the victims’ and vice versa. For example, a suspect may pick up carpet fibers on his shoes or leave hairs behind at a crime scene.

•  Hairs can be examined to identify their origin, such as human or animal. Hairs with roots intact can be tested for DNA.

• Fibers are used to make clothing, carpeting, furniture, beds, and blankets. They may be natural fibers from plants or animals or synthetic fibers that are man-made.

Microscopic Image of Hairs & Fibers

Explain and demonstrate proper bagging and marking of all evidence.

• Packaging evidence separately prevents damage through contact and prevents cross-contamination. All items should be carefully packaged and marked upon their retrieval at crime sites.

• Normally, the collector’s initials & date of collection are inscribed directly on the article.

• The evidence container must also be marked with collector’s initials, location of evidence, & date of collection.

Druggist Fold

• Consists of folding one end of the paper over one third, then folding the other end one third over that, and repeating the process from the other two sides.

• After the paper is folded in this manner, the outside two edges are tucked into each other to produce a closed container that keeps specimen from falling out.

Follow chain of custody protocols

• Always use gloves and never move anything before it has been recorded by sketch or photo.

• You must document the evidence from the time it is discovered until it is produced in court

Draw a crime scene sketch using proper measurements, symbols and labels

• Demonstrate proper use of measurements.• The typical sketch is presented as a bird’s eye view of the scene.• The investigator must decide what scale to use. use the largest

scale possible. To determine what scale to use, divide the longest measurement at the scene by the longest measurement of the sketching paper to be used. Most reports and records are kept on 81/2 X11-inch paper. Thus if the longest measurement at the scene is 100 feet, let 1 inch equal 10 feet so that the drawing will fit comfortably within the 11-inch length of the paper.

• All sketches should include a compass or an orienting compass arrow indicating north; a legend or key to explain letters, numbers, or symbols used; and an indication of the scale used

Sketch Methods• Rectangle coordinates method requires two reference lines at right angles to each other. Often

used to locate objects in the room. • Triangulation method requires measuring the distance of an object from two fixed reference points.

In a room, the corners are the fixed objects and the locations of objects are recorded by their distances from the two points.

• Base line method requires measurement to be taken from a single reference line.

The base line should be established by using a length of string. The measurements indicating the location of a given object are then taken from left to right alond the baseline to a point ar right angles to the objects being plotted.

• Compass point method requires a protractor. The corner of a room, is selected as the point of

origin. A line extending from the origin is used as an axis from which angles can be measured. • Cross projection method the crime scene takes on the appearance of a box opened out. The ceiling

opens up like the lid of a hinged box, with the four walls opening outward. In some law enforcement circles, this method is also called an exploded sketch. It is an effective way to portray evidence found on or in the walls or ceiling of a room

EQ: How do investigators record and preserve a crime scene? 34

Sketches• Rough sketch at crime scene• Show location of all items that have

any bearing on the crime• Dimensions and measurements must

be 100% accurate–use tape measure–measure from 2 fixed points