Preliminaries, Photographing & Documentation - pgs 23-36 Trace evidence is as important to solving a crime as substantial evidence such as the weapon used

Preliminaries, Photographing & Documentation - pgs 23-36

• Trace evidence is as important to solving a crime as substantial evidence such as the weapon used or the victim.

• Remember Locard’s Exchange Principle from page 10

• Crime scene investigation consists of preliminaries, documentation, collection & preservation, and legal considerations

Preliminariespgs 23-26

• “First things First”

• Recommended preliminary actions:

• 1. Deal with any emergency situation that is found (person needing first aid or a weapon that needs to be secured) regardless of the following guidelines.


• 2. Identify the person who reported the crime or disturbance to the police and if possible detain the person for questioning.

• The individual may have valuable information and may even become a suspect.

• 3. Attempt to determine the perpetrator of the crime if that can be immediately determined by inquiry or direct observation


• 4. Detain everyone who is present at the scene, including eyewitnesses to events leading up to the crime, to the crime itself, or to its aftermath or people in possession of other information that must be collected while fresh.

• 5.Summon whatever assistance may be necessary – crowd control or safeguarding the area.


• 6. Secure the scene by issuance of necessary orders & by physical isolation of the area.

• Keep away unauthorized personnel, rope off scene.

• All witnesses should immediately be referred to an investigator


• 7. Separate the witnesses so that their statements are not influenced by one another.

• 8. Secure and investigate any additional crime scene, such as place from which a body was moved or where a vehicle connected to the crime is discovered


• 9. If it is known there is no emergency, avoid rushing to the area of focus such as body in a homicide case. Work from the outside inward. Minute but valuable evidence may be altered or destroyed.

• 10. Refrain from moving or even touching any object at the scene. It is impossible to restore an item of evidence to its original position once it has been moved.


• 11. If assistants are available, assign each one definite duties so as to minimize confusion & eliminate duplication of effort.

• Assignments for assistants: officer in charge, assistant (to officer in charge), photographer, sketcher, master note taker, evidence person, measurer, section leader


• Officer in charge – assumes overall responsibility, gives directions, delegates assignments

• Assistant – carries out directions of the officer in charge

• Photographer – takes the necessary photos of the scene as well as of each individual item of evidence as it is discovered


• Sketcher – prepares a rough draft and later a finished drawing of the crime scene

• Master note taker – records in short hand and such observations and descriptions as other provide, noting the time at which a discovery is made and by whom, and keeps a well ordered log of the activities


• Evidence person – collects, tags, and preserves each item of evidence

• Measurer – takes general measurements of scene that sketcher will need; also locates by a suitable means such as a coordinate system every significant object and each item of evidence that is present


• Section Leader – takes charge of personnel in a section (usually made up of 6 individuals) whenever a large scene must be searched in teams and makes arrangements for collecting, preserving, and transporting any evidence that is discovered.


• In reality, the majority of crime scenes are usually handled by one or two technicians and possibly a supervisor

Documentationpgs 26-32

• Documentation consists of photographs, crime scene sketch, and notes

• Photographs – a good photographic record helps document the facts and physical circumstances at the crime scene, records evidence, permits reconstruction of the crime & reveals evidence that might otherwise be missed.


• Photographs have criteria to meet also.

• Should be made before other stages of investigation are carried out.

• Should be taken of the entire area before anything is touched or removed.

• Taken from every possible angle together with close-ups of anything that might have a bearing on solving the crime.


• Camera position should be recorded on crime scene sketch or in the report made from on-site notes.

• Photos should be taken in overlapping segments that flow in one direction around the room or other area, with the camera approximately at eye level (unless tripod is used).

• People should not appear in photographs


• Correct photographic perspective must be maintained to prevent distortion from reducing or even destroying a photograph’s evidentiary value

• Most authorities advise taking pictures both with and without ruler for scale aids.

• Make more photos than may seem strictly necessary


• Before being removed from crime scene, items of evidence (murder weapon, blood stain) should be photographed at close range (to show the object clearly), then at a distance sufficient to place an object in proper context.


• Required photos by book Criminal Investigation are as follows.

• 1. line of approach to and flight from scene• 2. Significant adjacent areas, such as yard

of house in which homicide occurred• 3. Close-up photographs of the entrance &

exit to the house used by the suspect or those most likely to have been used if these are not obvious


• 4. General scenario photograph showing location of the body & its position in relation to the room in which it is found

• 5. At least two photographs of the body, at 90 degree angles to each other, with the camera positioned as high as possible, pointing downward toward the body


• 6. As many close-ups of the body as needed to show wounds or injuries, weapons lying nearby, and the immediate surroundings

• 7. Area underneath the body and under each item of evidence immediately after its removal. If there is any mark, stain or other apparent alteration produced by the presences of the body or evidence


• 8. All blood stains, preferably in color• 9. All latent fingerprints after dusting and before

they are lifted and the weapons on which the prints were found, showing each print’s relationship to the general surroundings. (Latent fingerprints likely to be destroyed by lifting always must be photographed, even when it is not standard practice to shoot all fingerprints before handling.)


• In the case of buried bodies, any evidentiary item discovered en route to the site – such as tire tracks or articles of clothing – should be photographed in situ (in their original place).

• After photographing the site, investigators should use stakes and strings to superimpose on the site a grid, which is usually oriented to north


• Soil should be removed carefully in even layers of about 4 – 6 inches using a hand trowel or flat bladed spade.

• Dirt should be sifted as it is removed first through quarter-inch mesh screen followed by sifting through ordinary window screening.

• Items should be photographed in situ as discovered both with ruler and north indicator and without.


• Items found on screens should be photographed there (with scale but not north indicator)

• They should never be returned to the excavation for photographing; that would constitute false documentation


• The Crime-Scene Sketch complements the photos and notes made during the search of the crime scene.

• Advantages of sketch: displays areas that photographs cannot such as floor plan of a house; ties together multiple, rather fragmented, views and eliminates distortion caused by perspective.


• More advantages of sketch: It eliminates unnecessary detail so that essential elements are shown clearly;

• Illustrates the location of evidence such as latent fingerprint that isn’t visible in photos

• It can be used to plot accurate measurements made at the scene.


• Rough sketch is a rough sketch• Graph paper is an aid to accuracy and

proportion and easily fixed to a clipboard.• Steel tape measure and a magnetic

compass are needed as well as a soft lead pencil and eraser for corrections.

• No changes should be made to the original sketch after the investigator has left the scene


• Methods used to locate points on a sketch are rectangular coordinates or polar coordinates

• Rectangular coordinates – 2 perpendicular lines are used such as walls in a room. Original position of item of evidence can be located by measuring at right angles its distance to each wall. Two intersecting streets may be used for exterior work.


• Polar coordinates – a fixed point is chosen such as an electric pole and a desired object is located by distance and compass reading

• Positions can later be plotted accurately on the finished drawing by use of a protractor


• A good final drawing will include the following information:

• 1. The name and if applicable the rank and shield number of the investigator who prepared it.

• 2. The date and time of the sketch, the crime classification, and case number

• 3. The full name of anyone who assisted in taking measurements.


• 4. The crime scene’s address location inside a building, nearby landmarks, and an arrow indicating north.

• 5. The drawing’s scale (1 inch = 1 foot)• 6. The location with accurate measurements of

every major item of evidence and all other important features at the scene

• 7. A legend of the symbols used to identify points of interest on the drawing.


• Color may be used but not to the point of confusion.

• Accuracy is of the utmost importance.

• The Note-taker keeps a log that records the time of discovery of the crime, the identity of the person reporting it, observations and descriptions provided by others.


• Notes should be sufficiently detailed to anticipate the need of refreshing one’s memory months or even years after the crime has been processed.

• Detailed notes can be taped much faster (audio &/or video) than they can be written.

• At some point, the tape must be transcribed.

Collection and Preservationpgs 32-36

• The Grid Method – standard procedure for covering large areas.

• Number of variations such as searchers walking in parallel rows either horizontally or vertically shifting rows to new locations as necessary until the search area has been completely covered.

• Repeat the search at right angles to the first


• The Zone Method - Indoor scenes will quite naturally be searched on a room-by-room basis with each room subdivided as necessary into squares or sectors, and where desirable, each sector further divided.


• When searching the crime scene you are looking for anything that will shed light on the corpus delicti or the fact that the crime in question was indeed committed (money bag).

• Also trying to determine the perpetrator’s modus operandi or “M.O.” or method of operation such as a glass cutter for illegal entry.


• In collecting evidence, care should be taken to acquire adequate samples sufficient for a battery of tests by the lab and additional analyses by the defense with a quantity left over for any future review or retrial.

• Collect control samples: specimens of any foreign substance or background material may have been contaminated by the stain


• Integrity of samples must be maintained. Any evidence sample be kept from contact with any other sample or contaminating material.

• To maintain individuality each piece of evidence should be separately wrapped & shouldn’t share the same container unless all danger of mingling is removed by the employment of strong protective coverings or partitions.


• To preserve evidence samples, they should be kept from high temps and should be placed in storage as soon as possible. If perishable, it may require preservatives but used only with expert knowledge.

• Trace evidence – hairs and fibers, dirt, filings, or other particulate matter


• Trace evidence - picked up with a forceps or spatula & placed in bottles with snap-on tops or loosely wrapped in filter paper & placed in a pillbox.

• Documents & fingerprints on paper - placed without folding in cellophane envelopes.

• Bullets & shell cases - be surrounded with cotton in separate pill bottles or boxes.


• Clothing should have any stains or other points of interest widely encircled with chalk to call attention of the laboratory expert to them.

• Garments should be folded carefully with clean white paper inserted between stains, and placed in a suitable clean box for transportation.


• Liquid blood should be deposited in a test tube using an eye dropper, and saline solution should be added in a ration of one part saline to five parts blood.

• Firearms, knives, & tools may be secured with string to a board having perforations for securing.


• If fingerprints already lifted, item may be wrapped in paper & placed in a sturdy box.

• In removing paint, wooden implement (a tongue depressor) should be used. Metal tool could leave traces that would interfere with spectrographic analysis. If necessary, a steel scalpel may be used & then delivered with samples to the lab expert.


• Marked or unmarked items are further protected by being sealed in containers in such a way that the seals must be broken for the containers to be opened.

• Investigator’s name or initials & abbreviated date should be written in ink on the seal. An adhesive label should be affixed to box or envelope or tag attached to marked rifle bearing case information.


• Case information:• 1. case number• 2. date and time item was found• 3. item’s name and description• 4. location of item and when discovered• 5. signature of investigator who discovered

item• 6. names of witnesses to the discovery


• Special care must be taken in transporting evidence so it’s not altered or damaged in transit.

• Evidence should be deposited in a secure evidence storage facility and remain there except when removed for legitimate purpose such as lab examination or use as evidence at a trial.


• Each time item is removed/deposited, following should be recorded in ink in log:

• 1. date evidence was received in storage• 2. case file number• 3. case title• 4. person from whom or place from which

item was received• 5. name of staff person received the

evidence


• 6. complete description of evidence including identifying data – serial number

• 7. disposition whether to an individual (named) or other

• 8. signature of officer in charge of evidence room

Crime Reconstructionpgs 37-40

• The investigator should attempt to determine sequence of events that constituted the crime – this is called reconstruction.

• First step is to reconstruct scene’s physical appearance & should be enough to give accurate indication of the crime.

• Construction should be carried out under similar circumstances.

Crime Reconstructionpgs 37-40

• After the physical reconstruction, investigator attempts to reach conclusions about various, perhaps conflicting, testimony & physical evidence.

• A theory should not be rejected merely because investigator might not under the circumstances behave in a similar manner. Study should be conducted from the point of view of the mentality of the criminal.

Blood Patternspgs 38-40

• The nature of blood evidence plays a crucial role in many reconstructions of violent crimes.

• Different ways bloodstains appear when blood leaves he body & is transferred to a surface has led to a criminalistics subspecialty known as blood-pattern analysis.


• Blood pattern evidence may reveal whose blood is present, type and order of injuries, type of weapon that caused each injury, whether the victim was in motion, when an injury occurred, whether he or she move – or was moved - afterward


• Blood is an aerodynamically uniform material whose behavior is not significantly affected by temperature, atmospheric pressure, or humidity

• Scalloped edges generally indicate a greater distance of falling than do perfectly round edges, given the same target surface.


• The directionality of a small bloodstain or droplet is easily determinable from its uniform tear-drop shape, with its tail pointing in the direction of travel.

• Cast-off droplets – secondary spatter from a larger drop; these droplets have longer tadpole shapes with the sharper ends pointing toward the direction from which they came.


• If no larger drop is present among hundreds of drops less than 1/8” across, one may conclude that the pattern resulted from an impact.

• Blowback – blood spattering on the weapon at the time of firing, indicating that the pistol was very close to the victim when it was fired.


• The process of conducting on-scene blood-pattern analysis is exacting work involving photographing & measuring each blood droplet and using a formula to calculate the impact angle.

• “No More Strings” – forensic computer software program that uses a special protractor to determine blood droplets’ angles of travels & enters into the problem to give a simulated 3-D view of area with lines drawn to indicate each stain’s origin.

Legal Considerationspgs 40-43

• Due to O.J. Simpson trial in 1995, criminalists and investigators now have an almost impossible burden added to their load: they must prove they did not falsify evidence.

• Accusations included mishandling evidence, contaminating evidence, planting evidence, lied about who collected blood sample evidence


• Another issue that arose during the O.J. Simpson case was unreasonable search and seizure.

• Fourth Amendment to U.S. Constitution regulates the right of search and seizure unless you have “probable cause”.


• “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath of affirmation, and particularly describing the place to be searched, and the person or things to be seized.” – from U. S. Constitution


• Probable cause - “a reasonable ground for belief, less than evidence justifying a conviction, but more than bare suspicion.

• Police may search without a warrant only in an emergency, or when securing evidence from imminent destruction, or with the consent of the parties involved, or when searching a lawfully arrested person &/or property within his immediate control.


• Subsequent reentries without a warrant are invalid, & the evidence collected on those occasions is inadmissible.

• To prevent the exclusion in court of evidence on some real or perceived grounds, the documentation of a crime scene must be careful & accurate, & physical evidence must be collected thoroughly.


• Control samples must be collected, evidence preserved kept free from contamination, marked properly, and logged consistently.

• Chain of custody must be rigidly maintained.

Case Study: The Jeffrey MacDonald Case pgs 43-50

• MacDonald’s wife and kids killed.

• MacDonald was sole survivor.

• He told MPs there were 4 assailants, 2 white males, one black & one white female

• He had 2 slight knife cuts, a “neat, clean incision” between two ribs that had punctured a lung, a bump on his head, and a few fingernail scratches


• He stated he was hit with a baseball bat and stabbed with an ice pick, wrestled the assailant(s) and passed out.

• He woke to find his family dead.• Only things out of place were a coffee

table and spilled flowerpot.• Murder weapons were club, ice pick &

paring knife husband pulled out of wife’s chest to perform CPR


• Blue threads found on club and on wife as well as bedroom rug around her body as well as kids’ bedrooms. None found in living room where husband had pajama top ripped off.

• No blood found in hall where he supposedly passed out. All four family members had different blood types.


• Wife’s blood found in footprint in child’s room – she was killed first.

• No physical evidence of intruders

• Father had extramarital affairs & lied about owning an ice pick.

• Charges dismissed for insufficient evidence only to be brought back 4 years later


• Defense argued double jeopardy and right to speedy trial was not given

• Almost a decade after murders, MacDonald was brought to trial which lasted 7 weeks.

• Jury deliberated for 6.5 hours. He was found guilty of 2nd degree murder of wife & one daughter & 1st degree of other daughter


• Sentenced to three consecutive life sentences.

• Defense asked Judith Bunker, nationally known blood-pattern analyst, to testify for MacDonald.

• Her answer: “No. My testimony would only hurt your client.”