MMSC 240: EXAM 1

cardinal rule #1 → fill the frame

- "fill the frame" has two aspects, both a positive and a negative • the positive aspect is getting closer in order to gather more detail in your photograph • the negative aspect is reducing or eliminating irrelevant detail in your photograph in an attempt to improve your photograph - get close to the primary subject • zoom in, or get closer, to eliminate unwanted or unneeded areas/ objects around the primary subject • compose it with the appropriate horizontal or vertical camera viewpoint • avoid having the primary subject so close to the edge of the photograph that parts are cut off in the print

initial walk-through/ preliminary assessment of the crime scene

- "look — but don't touch" - the walk-through: initial survey of the crime scene • ask the first responder what happened • jotting down what you see at the scene - the initial walk-through is the opportunity to determine the nature and extent of the crime • assessment of what has to be performed at the scene (blood swabs, fingerprints, etc.)

The International Association for Identification (IAI)

- "no valid basis exists for requiring a predetermined minimum number of friction ridge characters which must be present in two impressions in order to establish positive identification"

ninhydrin

- Ruhemann's purple - reacts with amino acids to produce a purple-colored impression - extremely effective on a wide range of porous surfaces - cons • fume hood or outdoor environment is a must → it is a carcinogen • short shelf life • offensive smell - use • spray or dip your porous item • allow to sit for 24 hours

small particle reagent (SPR)

- SPR is a liquid with molybdenum disulfide suspended in it - sprayed on the surface - dried it can be lifted with lifting tape - example: wet motor vehicle

Automated Fingerprint Identification System (AFIS)

- a biometric identification (ID) methodology - uses digital imaging technology to obtain, store, and analyze fingerprint data - the AFIS was originally used by the U.S. Federal Bureau of Investigation (FBI) in criminal cases - the heart of AFIS technology is the ability of a computer to scan and digitally encode fingerprints so that they can be subject to high-speed computer processing - aids in classifying and retrieving fingerprints by converting the image of a fingerprint into digital minutiae that contain data showing ridges at their points of termination (ridge endings) and their branching into two ridges (bifurcations) - when the search is complete (a computer can make thousands of comparisons per second), the computer produces a list of file prints that must be examined by a trained fingerprint expert

chain of custody

- a list of all persons who came into possession of an item of evidence - continuity of possession, or the chain of custody, must be established whenever evidence is presented in court as an exhibit • a date and time must be stated - adherence to standard procedures in recording the location of evidence, marking it for identification, and properly completing evidence submission forms for laboratory analysis is critical to chain of custody - this means that every person who handled or examined the evidence and where it is at all times must be accounted for - OJ Effect • facts of the case do not favor the Defense, so they focus attack on individual items of evidence, proper handling, and chain of custody • can't attack the facts → attack the evidence - CSI Effect • unrealistic expectations on behalf of jury, mostly as a result of entertainment shows • have to be able to articulate reasonings behind why it was conducted

what is a rolled fingerprint?

- a rolled fingerprint is a reproduction of the ridges of the finger created by rolling that finger in a thin medium of ink or on a livescan scanner plate, and then transferring them to a recipient surface, creating a permanent recording of the friction skin characteristics - intentional copying of a fingerprint - known prints are in the system

a single barrier perimeter

- a single barrier is fine for initial purposes - it does not provide a sufficient buffer for long term scene effort • secondary area for cops and other law enforcement • outside secondary area = everyone else (media, general personnel)

assessing crime scene hazards

- a variety of hazards to the crime scene technician exist in the scene. these include: • bio-hazards from blood or bodily fluids • structural hazards in fire and explosion scenes • chemical and inhalation hazards in fire scenes • inhalation and chemical hazards from on-scene processing techniques • inhalation and explosion hazards associated to drug labs • bio-chemical hazards associated with terrorism

environment

- air, temperature, and water all have an effect on the survivability of latent prints, and their successful development - if the surface is hot, it may cause rapid evaporation. a cold surface can eventually create condensation - an individual perspires less during low temperatures

general fingerprint patterns

- all fingerprints are divided into 3 classes of general patterns - loops → 60-65% of the population - whorls → 30-35% of the population - arches → only about 5% of the population

loops

- all loops must have one delta, which is the ridge point at or directly in front of the point where two ridge lines (type lines) diverge • delta = triangle - ulnar loop: flowing toward the little/ pinky finger - radial loop: flowing toward the thumb - both loops and whorls have identifying characteristics known as the core and delta

safety precautions for ninhydrin

- all necessary precautions associated with any solvent - no skin contact - do not breathe - will dye your skin

perspiration/ sweat

- amount of sweat transferred from the skin to the object touched is the main factor bearing on the identifiably of latent prints - 98.5-99.5% water, and 0.5-1.5% solid matter - there may be insufficient perspiration to which developing agents can adhere - when sufficient perspiration accumulates on the skin, it should yield a clear impression to which developing reagents will adhere - anxiousness or nervousness of the individual may also have an effect on the secretion of perspiration through the pores - an individual perspires less during low temperatures

oblique flash sequence

- at what angle should the flash be held? • this angle is best determined by viewing the imprint from directly overhead while you move a flashlight through various angles, watching as different shadows are created with the different flashlight positions - from how many locations around the impression should the flash be aimed at the impression? • the best answer is to fire a series of flashed between each of the three tripod legs

baseline mapping

- baseline created from a datum point - evidence measured at right angles to the baseline - one measurement required - best utilized in exterior scenes with limited landmarks - baseline is extended from a datum point in a cardinal direction - a single measurement is made from the evidence to the baseline at a right angle - inappropriate for typical interior scenes

basic techniques for fingerprint collection

- basic scene fingerprinting techniques include: • brush and powder • super-glue fuming/ cyanoacrylate • small particle reagent (SPR) → currently wet surfaces • rough surface casting gel or silicon • ninhydrin → porous surfaces

triangulation mapping

- best utilized in scenes with evident landmarks • good reference points - 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 object's shape is regular or irregular • regular = an item that CANNOT be molded will have 4 measurements • irregular = an item that can be molded/ change shape will have 2 measurements - utilizes two or more reference points to establish the position of an object - by drawing a line that connects the two reference points and extending a line from each of the reference points to the object being measured, a triangle is formed - evidence measure from two known points (regular shaped object) or center of mass (irregular objects) to two known room landmarks - 2-4 measurements required

bounce flash

- bounce flash: aiming the electronic flash at a ceiling or side wall to soften the light reaching the primary subject, because the farther light travels to reach a subject, the softer (dimmer) it will be when it gets there • the photographer may have to compensate for the dimmer light - where do we aim the flash? • the optimal location on the ceiling to aim the flash, to minimize the total distance the light has to travel, is at a point that is midway between the photographer and the subject matter • the flash head should not be positioned to bounce the light beyond the half point. this would cause the light to bounce down behind our subject of interest and may either backlight our subject and throw him or her into shadow, or the light may not light them at all

safety for superglue fuming

- can bond to your eyes, mucus membranes or mouth ... ALWAYS use adequate ventilation - overheating superglue will produce cyanide gas ... NEVER go over 200 degrees Fahrenheit - studies have shown some people develop a hypersensitivity to the fumes over time, suggesting the effects are cumulative

components of superglue chamber

- chamber - super glue gas - humidity - gas circulation

surface characteristics

- characteristics of the surface in question define the fingerprinting method - the four basic conditions are: • porous → paper, cardboard, untreated wood • non-porous smooth → painted, plastic, or glass surfaces • non-porous rough → vinyl, leather, textured countertops • special conditions → skin, adhesive tape

close-up photographs

- close-up photographs are taken last and show greater detail of individual objects or evidence • taken at a 90º angle to the object, with and without evidence markers and scales • scales should be place as close to the evidence as possible without affecting it in any way - after the 90º photographs have been taken, photographs from other angles may be taken - the most important close-up photographs are those depicting injuries and weapons lying near a body - after the body is removed from the scene, the surface beneath the body should be photographed

in situ photographs

- close-ups: "as found", "as is" • the first close-up photograph should show the evidence "as found" in the scene before any alteration or movement of anything in the scene

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

processing factors

- condition of the surface and the limited smooth area available for processing - superimposed or smudged because of the way an item or evidence is handled - surface is dirty, oily, or greasy - while many investigators wear gloves when handling evidence, these is always the risk that they may become careless and destroy prints

confusion issues

- 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 blood stains - photo logs help prevent an issue of what photograph was first

crime scene mapping techniques

- crime scene mapping is the process of measuring and recording the actual location of evidence - the most common mapping methods include: • baseline coordinates • rectangular coordinates • triangulation • polar coordinates • triangulation or rectangular coordinates on a grid • triangulation on a baseline

crime scene photography

- crime scene photographs should record the area in which the crime actually took place and all adjacent areas where important acts occurred - the most important prerequisite for photographing a crime scene is for it to be in unaltered condition - each crime scene should be photographed as completely as possible in a logical succession. the sequence will show the overall scene first, then work down to individual pieces of evidence that jurors in the trial can easily relate back to the larger scene - the four minimum photographs required at the crime scene: • overview photograph • a medium range photograph • a close-up photograph • a close-up photograph with a scale

recurring problems in photography

- crime scene photography has four recurring problems that detract from its value. these are: • identification issues • orientation issues • confusion issues • incomplete documentation issues - any of these can detract from the viewers understanding of the scene

crime scene sketching and mapping

- crime scene sketching is the act of drawing a two dimensional view of the scene and important artifacts - crime scene mapping is the process of measuring and recording the associated locations of these elements in the scene • maps have to have dimensions/ values of distance - one can sketch without mapping, but rarely does one map without sketching - the most critical step in the process of creating a crime scene diagram is accurately measuring the position of every item depicted in the rough sketch - every item included in the rough sketch should be measured from one or more reference points • reference points = a fixed point - the number will depend upon the method used to measure the scene - before any measurements are taken, the measurement method must be determined and reference points must be established

super glue fingerprinting

- cyanoacrylate fuming also called "super glue" is a technique that stabilizes latent prints - object exposed to super glue fumes, which harden the print - the print is lifted in typical fashion (e.g. brush and powder, lab dyes)

cardinal rule #2 → maximize depth of field

- depth of field is the variable range, from foreground to background, of what appears to be in focus. the depth of field can encompass any volume of range, from one item of evidence to an entire scene - focusing to maximize depth of field is one distinguishing feature of crime scene photographers that separates them from other photographers • if things are out of focus, it isn't a "fair and accurate representation of the scene" • a defense attorney may successfully argue that exculpatory evidence was located in the area currently appearing to be out of focus - a defense attorney may be able to successfully argue that the photographer was too incompetent to create a properly focused image, and the images should be excluded as being substandard and unprofessional

history → super glue fuming

- developed in the Prefectural Crime Lab of the National Police Agency of Japan - scientists working in trace noticed his fingerprints developing on microscopic slides when he used superglue to mount hair to slides - '79, US Army working joint investigation with Japan while they demonstrated a "secret chemical for developing latent fingerprints" - Japanese did not realize on of the officers could read Katakana - bottle read aron-arufa, discovered to be superglue - mid 80's, research is done into accelerating the process with heat and chemicals

photograph methodology

- document the entire scene in-situ (as found) 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 and evidence close-up photos - as items are discovered in later stages, return and document them fully, including additional overall photographs if needed

typical sketch drawing

- drawn in a "birds-eye" view - easily demonstrates items in a horizontal plane (e.g. floors, beds) - numbers are next to points of interest/ evidence which are described in the legend

elevation sketch drawing

- drawn in a "side" view - demonstrates items on vertical planes (e.g. walls, pictures) • only show the walls that have evidence on them

latent fingerprints

- each skin ridge is populated with pores leading to sweat glands, from which perspiration is deposited on the skin • can transfer prints through sweat onto certain surfaces - once the finger touches a surface, perspiration along with oils that may have been picked up by touching the hairy portions of the body, is transferred onto that surface, leaving the finger's ridge pattern (a fingerprint). prints deposited in this manner are invisible to the naked eye and are commonly referred to as a latent print

baseline method

- establish a single reference point - a tape measure is then extended (parallel to the scene) from the reference point to an end point, beyond the entirety of the scene - most often established along a curb or sidewalk in order to simplify the measurement process - measurements are then made from a point on the tape to an object in the scene at 90 degree angle

perimeter

- establish and secure a crime scene perimeter (tape, vehicle or any other artificial barrier) - bigger is better. the perimeter can be reduced later. the initial perimeter should be as big as you can control

defining an initial perimeter

- every crime scene is different, but there are three factors that help the officer identify the initial perimeter - these factors or areas of consideration are: • primary focal points → bodies, weapon, location • natural entry and exit points • secondary scenes → cars, dumpsite, etc.

strip search

- excellent in exterior scenes where a large area must be examined • outside areas • by yourself - visual alignments to the strip 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 strips with string or tape can help maintain the order

circle (a.k.a. spiral) search

- excellent pattern in most interior or confined exterior scenes - not effective in large exterior scenes or cluttered areas that impact on the circular movement - searcher moves inward or outward from a starting point - narrowing circle: starting from the outside working in to the middle of the circle - widening circle: starting from the middle and working outward

exterior overall photographs

- exterior overall photographs: these photographs relate the exterior of the crime scene to the general surrounding area. if the crime was committed indoors, they also show external views of the building in which the crime occurred • views toward the building • views from the building - five reasons exist why the compositions with the film plane parallel to a wall are preferred over diagonal viewpoints: • diagonal viewpoints have the near side of the building appear larger than the far side • a depth of field problem is created • flash lighting will not be equal over entire building • parallel shows means of ingress and egress more adequately • fixed features are better seen when photographed parallel - taking exterior overall photographs at the beginning of the crime scene documentation is productive because these locations are usually open to the public's view and not usually subject to any possible subject's reasonable expectation of privacy

environmental conditions

- extreme hot 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

brush and powder

- finely milled particles are applied with a brush, attaching to the latent print - this includes magnetic powders and fluorescent powders - powdered latent is photographed and lifted with lifting tape

fingerprint science

- fingerprints • general patterns • factors affecting the deposition of latent prints on an item • basic processing techniques • AFIS

recovering fingerprints

- fingerprints always begins as a search, looking for: • (visible) latent prints • patent prints • disturbed areas - once these areas of concern are found, the decision of "how" to fingerprint must be examined

the crime scene

- first responsibilities • make sure the criminal isn't there / clear the scene • medical help • secure the crime scene (perimeter)

personal protective equipment (PPE)

- goggles/ eye protection — splash and mucous membrane tissue protection - face/ particle mask — inhalation protection - tyvek suit — impervious to liquid contaminants - rubber gloves — impervious to liquid contaminants - booties — splash and contact protection for footwear

identification issues

- identification issues involving 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

adhesive surfaces sequencing

- important to address the fact that there are two different sides to the tape and that will take two different processes - best for slick side will most likely be fuming - best for stick side is wet wop - solutions • place sticky side down on silicone paper or nonstick aluminum foil to protect that side • fume exposed slick side • allow glue to cure 24 hours • treat sticky side with appropriate wet process º wet wop º sticky side powder º simple solution

minutiae

- in fingerprinting terms, the points of interest in a fingerprint, such as bifurcations and ridge endings • needed to make a positive identification of the print - the individuality of a fingerprint is not determined by its general shape or pattern, but by the careful study of its ridge characteristics, known as minutiae - it is the identity, number, and relative location of these minutiae that imparts individuality to a fingerprint - there are as many as 150 minutiae on the average finger - currently in the United States, there is NO predetermined minimum number of friction ridge characters which must be present in two impressions in order to establish positive identification • should try to have at least 10 identifiers to make a positive match if possible - ridge endings: a ridge that ends abruptly - ridge bifurcation: a single ridge that divides into two ridges • looks like a Y/ fork - short ridges (island): a ridge that commences, travels a short distance and then ends - enclosure: a single ridge that bifurcates and reunites shortly afterward to continue as a single ridge • oval in a ridge line

size of the item being sought

- in focused searches the size of the item being sought can affect the size of a search swathe - 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, its another to look for a shell casing

incomplete documentation issues

- incomplete documentation 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 eliminate this issue

provide emergency care

- initial responders have a duty to act in the interest of victims or potential victims - crime scene security may have to wait - primary rule of emergency care is: • life saving always takes priority over evidence preservation - for the sake of evidence preservation, initial responders do not have the authority to prevent EMS access to a scene - if ambulance crew is on scene, • determine what alterations have been made such as when and what was moved • identify all EMS personnel on scene → must identify evidence that may have been left by the medical team • limit access to the scene to those who have an absolute and official necessity to enter = crime scene log

interior overall photographs

- interior overall photographs: these are the bridge between the exterior overall photographs and the individual items of evidence within the crime scene. after the exterior has been photographed and before evidence is photographed, the interior is photographed - old mindset → diagonal shots from each corner • has many of the same problems as diagonal exterior overall shots - new mindset → film plane parallel • more fair and accurate representation of the scene

irregular shaped triangulation map

- irregular shaped objects have irregular shapes with no specific points or shapes that will change with movement (e.g. blood pools, clothing pile) - irregular shaped objects require two straight line measurements from two distinct landmarks in the room to the center of mass on the item - this fixes the item as effectively as is possible in the scene

crime scene safety

- it is recommended that personnel always wear latex (Nitrile) gloves and possibly chemical resistant clothing, Tyvek-type shoe covers, a particle mask/respirator, goggles, or face shields when potentially infectious material is present. gloves should be changed often • do NOT want to cross contaminate the evidence - personnel should maintain a red biohazard plastic bag for the disposal of contaminated gloves, clothing, masks, pencils, wrapping paper, and so on

types of prints

- latent print: a print that is not visible to the human eye - patent print: a print that is visible to the human eye - plastic print: a print that is in 3D (blood print, wax or heavy contamination)

bodies and wounds

- like any other item of evidence, a body at the crime scene has to be fully documented - after the midrange photograph of a body, a complete body panorama series is photographed • overhead shot • full-face shot/ profiles º goal is to provide means by which to identify the victim º face should be parallel to film plane º fill the frame with the face • close-ups of the body - composite photographs of bodies: • sometimes you cannot manage to get the entire right or left side of the body in your field of view • divide the body into two shots º head to waist º waist to feet - after the photographic documentation of the entire body, documenting the wounds to the body is next in order - it is necessary to take a midrange photograph of it showing the wound's relationship to a fixed feature of the body - then proceed to close-up photographs - when body is ready to be moved, the series of earlier photographs are repeated with the back of the body and the wounds that now become visible - the area that had previously been under the body is itself searched and will usually be photographically documented

fingerprints

- low percentage endeavor since a lot are not positive/ feasible prints - negative testimony: explain why NO fingerprints were recovered at the scene

ninhydrin acceleration

- many advocate the acceleration of ninhydrin development through heat and humidity - these units range from a steam iron to a $10k development chamber

multi-level containment

- multi-level containment involves two barriers which creates three areas of access: • inner scene: this is the actual crime scene, where only authorized investigators and crime scene technicians operate • working area: this is an area surrounding the inner scene, where other support police may enter, equipment is staged and evidence is brought to • outer area: this is everything on the outside of the second barrier, where on-lookers, media and others may gather - two perimeters provide three areas of access - this keeps support police out of the actual scene and others at a safe distance

[fingerprint] sequencing

- multiple processes can be done on the same item if they are done in the correct order - incorrect order of multiple processed is not possible, as it leads to a loss of information in the print - this is true for both porous and non-porous surfaces

orientation issues

- 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 (e.g. where is it in the scene) • photographs are taken in which orientation is not clear (e.g. which way is up?)

overall photographs

- 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 (e.g. tracked blood, movement of items)

midrange photographs

- overall photographs have been concerned with documenting the crime scene, both indoors and outdoors - with midrange photographs, we now begin to document individual evidence - the midrange photograph is also taken immediately before a series of close-up photographs of that particular item of evidence - these will only be informative if it is known where these close-ups are located within the scene - once an item of evidence has been selected to be documented, its midrange photograph is taken, followed by close-up photographs of the same item of evidence - also known as evidence establishing photographs - the evidence establishing photograph is not intended to show details, simply to frame the item with a known landmark in the scene - the close-up and the evidence establishing photograph go hand in hand - position yourself an equal distance between a FIXED object (reference point → doorframe), and your point of interest, in order to show realistic perspective - think of an isosceles triangle - don't be so concerned that the isosceles triangle point of view is established that you forget other composition ideas and include too much background in your image - fill the frame with just the subject matter at hand, eliminating extraneous elements from the composition

why do we photograph and video tape scenes?

- photographs are the best source of documenting scene accuracy - memorialize scene - tell the story, put the jury at the scene - trigger/ witness recollection of scene - investigative tool - reconstruction

what is friction skin?

- present on the palmer surfaces of the hands and fingers and on the planter areas of the feet on humans is skin, which is different from the skin on the other areas of the body. unlike skin of other areas of the body, this skin has raised ridges and indented furrows. these ridges aid in the finger's ability to grasp by increasing friction, thus the term "friction skin" - ridge lines make up our patterns (whorl, arch, loops)

primary focal points

- primary focal points are always obvious to the observant officer - they may include • the body or large blood pools • areas ransacked or disturbed • areas where evidence such as shell casings or money are strewn about and are immediately obvious - they are places the police are led or drawn to by their apparent association to the crime

physical evidence

- real, tangible - can be used in both criminal and civil trials - physical evidence can provide either class evidence or individual evidence • class → cannot discount OTHER contributors º ex: foot impressions (shoe molds), clothing (until matched with an individual) • individual → go to a specific individual º ex: fingerprints and footprints (skin to transferable surface) - crime scenes • primary scene → where the action occurs • secondary scene → travel agent/ dump site - transference of evidence: will leave and exchange evidence left behind and taken from the crime

regular shaped triangulation map

- regular shaped objects have fixed shapes that will not change with movement (e.g. guns, knives, furniture) - regular shaped objects require a total of four straight line measurements from two distinct landmarks in the room to two distinct points on the item • two lines from the tip/top of the object and barrel/ bottom - this fixes the item in a very specific position in the scene

what is the scientific basis for fingerprint identification?

- scientific basis is fingerprints are permanent and individually unique. every fingerprint of every person bears a ridge arrangement, which begins to form during the twelfth week of gestation. barring accidental or surgical removal, this ridge arrangement is non-changing for the life of the individual and will endure until decomposition of the body after death - alterations make the fingerprints MORE unique - twins • identical → have the same DNA but different fingerprints • fraternal → have different DNA and fingerprints

simple solution mixture

- simply mix black latent fingerprint powder with dish washing liquid into a pancake batter consistency - pour over sticky side of the adhesive - rinse with water

porous surfaces

- surface that will absorb water - raw wood - paper products - cloth

factors affecting the deposition of latent prints on an item

- sweat - surface - contact - environment

terrain and search swathe size

- terrain has a significant affect on the size of a search swathe

securing the crime scene

- the boundaries of the crime scene must be secured with crime scene tape, ropes, or cones • police cars, cops, etc. can act as a physical barrier for a scene - the secured area should include the area where the crime took place and the surrounding area where physical evidence may be located • make scene bigger and shrink down as investigation occurs based on facts and evidence - once the boundaries are secured, guards may be posted to restrict access to the crime scene - a detailed log is kept of personnel movements in and out of the crime scene. this log includes personnel names and time of entry or exit • job usually given to the youngest person

crime scene entry control log

- the crime scene entry control log identifies: • who entered the scene • when they entered, when they left • why they entered → for investigative purposes - this log is used to establish the integrity of the crime scene - the initial log may be nothing more than notes jotted down on a notebook, but it is an official record that others will review and examine - this record can help eliminate claims of crime scene integrity errors raised by Defense

going back in sequence

- the crime scene investigator is constantly encountering new evidence - this requires stepping back in the process to play catch-up • return to earlier step to bring the new evidence to a point where it makes sense and take videos, pictures, etc. to place it at the scene • example: by the collection step, all items have been photographed, sketched and documented in notes. if we move an object and find a blood fingerprint; we have to go back to earlier steps for that fingerprint making notes, photographing the item and sketching its location - this "going back" is a constant behavior. in both the search and collection phases it is routine to encounter new evidence - go back to an earlier step in the process - a failure to stop and go back, results in partial documentation. where critical information is lost and not documented • want to show interrelationships of items at the scene

the crime scene sketch

- the crime scene sketch graphically illustrates the layout, orientation and interrelationships of the scene and evidence • geographics of the scene - the standard crime scene sketch if drawn as a "birds-eye" view - the sketch may be a printed, to-scale document or it may be nothing more than a rough hand drawn sketch, with no scale at all • need a scale and key/legend • write "not to scale" if using approximate measurements

ensure officer safety

- the first responders cannot become casualties themselves - officer safety issues at a crime scene include: • crimes in progress or suspects still on scene. perform a protective sweep → without a warrant you can do a sweep of the scene to make sure perpetrator is NO longer there • natural hazards that may inhibit or harm the initial responder. oxygen? toxic? explosive hazard? • man-made hazards that might endanger initial responders → booby-traps to get rid of evidence

grid search

- the grid search is another variation on the strip search - searchers follow 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

photo documentation forms

- the labeled scale • can be preprinted or handwritten • use scale that will not influence exposure variables • whenever scales are used, they should be positioned on the same plane as the evidence they are associated with º ensures true measurement º eliminates depth of field problems

arches

- the least common of the three general patterns, are divided into two distinct groups • plain arches: a smooth flow of friction ridges • tented arches: a spike in the central pattern area - the plain arch is formed by ridges entering from one side of the print, rising and falling, and exiting on the opposite side (like a wave) - the tented arch is similar to the plain arch except that instead of rising smoothly at the center, there is a sharp upthrust or spike, or the ridges meet at an angle that is less than 90 degress - arches do not have type lines, deltas, or cores

preservation of fingerprint evidence for collection or preservation

- the primary concern in all cases is not to add anyone else's fingerprints to the evidence, or destroy the ones that may be present - when articles containing latents must be picked up, touch as little as possible, and then only in areas least likely to contain identifiable latents, such as rough surfaces

searching the crime scene

- the search for physical evidence at a crime scene must be thorough and systematic • particular order so that you don't miss anything - the search pattern selected will normally depend on the size and locale of the scene and the number of collectors participating in the search

search swathe size

- the search swathe is the area that any given searcher is viewing at any given moment in the search - how tight or 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

close-up with a fully labeled scale

- the second close-up photograph should be taken of every item of evidence is one that includes a fully labeled scale alongside the evidence - the scale must be on the same plane as the item of evidence - very important when taking photos of small items, whose detail may affect another analysis - ensure a good focus, make the pictures sharp

crime scene processing activities

- the six crime scene activities and their basic order are • 1) assessing • 2) observing • 3) documenting → notes, photos, sketches, reports • 4) searching • 5) collecting • 6) analyzing

variation in the sketch view

- the standard crime scene sketch is drawn as two-dimensional "birds-eye" view, thus items on horizontal surfaces (e.g. floors and tables) are easily indicated - two additional views allow the crime scene investigator to show additional details associated to vertical surfaces, these are: • elevation sketch → natural perspective, like watching tv • cross projection sketch → mix of birds eye and elevation

surveying the crime scene

- the walk-through — initial survey of the crime scene • obvious items of evidence are located and documented • the conditions of the scene are observed and recorded º special attention is paid to item or conditions that suggest timing of the incident or do not appear to belong

zone search

- the zone search is 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 º requires more than one person

search patterns

- there are five basic crime scene search patterns: • circle search • strip or line search • grid search • zone search - each pattern works in a variety of circumstances, but no single pattern works in every situation

essential elements of the sketch

- there are five essential elements included on a crime scene sketch, these are: • heading → a simple title that explains the purpose of the sketch (e.g. rough sketch depicted evidence and measurements) • diagram area → the actual sketch or drawing itself • legend → annotations that explain any symbols used in the sketch º use numbers or letters to list our evidence, the yellow tags • title block → administrative data, indicating case number, address of the location, date and time the sketch was prepared and by whom • scale and direction notations → annotations that indicate the direction north as depicted by the sketch and whether any scale was used º monumental in reconstruction º need directions (N, S, W, and E)

documenting

- there are four key elements in crime scene documentation, there are: • notes • photographs • sketches • reports - each is important in its own way. each supports and adds to the value of the other

sensitive photographs

- there will be times when wounds or injuries are located on parts of the body usually covered by a swimsuit. if the victim is still alive and will permit photographs of these wounds and injuries, several important concerns are related to the successful capture of this kind of evidence • permission • same-sex photographer • exclusion of unnecessary areas of skin

cardinal rules for crime scene photography

- three cardinal rules of good photography are key crime scene photography concepts: • fill the frame • maximize depth of field • keep the film plane parallel

crime scene protocol notes

- time and date of notification/ how notified/ by whom - time of arrival on the scene, weather conditions, climate, lighting, outdoor and indoor temperatures • important for decomposition - fixtures, doors, windows, gates, and their conditions (open/shut and locked/unlocked) - odors and other changing or deteriorating items (wet footprints, melting ice cream) • gives a timeline since it will eventually no longer be there - identification and appearance of persons in the crime scene - location and condition of items within the scene - items that were moved or changed, by whom, and for what purpose - appliances (off/on, hot/cold) - personal items — either missing or in-place (wallet, keys, shoes) - vehicles (engine hot/cold, doors locked/unlocked) • establishes a timeline - what tasks were performed and who completed those tasks

rectangular coordinate mapping

- typically used for measuring an indoor crime scene - to establish the position of an object in a room, measurements are taken from two different walls within the room that are perpendicular to one another - the tape measure is held perpendicular to the wall when the measurement is taken to ensure 90º angles from the wall to the object being measured - best utilized in interior scenes with clear boundaries (e.g. walls) - two measurements are made from the evidence to the surrounding walls and surfaces, at right angles - less precise than triangulation, as measurements are from center of mass (e.g. evidence can be rotated 360º on the center of mass) - wording • the pile of clothes are __#__ ft __#__ in. north of the south wall/ west of the east wall and vice versa

search considerations

- ultimately, some form of search must be conducted at the scene to locate evidence - the particular search pattern chosen is a function of the situation - no matter what search pattern is chosen the crime scene team must decide on a search swathe size

the "do nots" at a crime scene

- unnecessary walking about - moving or disturbing the bodies of victims - touching items or surfaces likely to yield latent impressions - allowing items to be removed from the scene - using the same entrance as the suspect - use toilet facilities - use towels - use the telephone - allow entry of unauthorized personnel - make statements to news media or public - conduct any search for physical evidence - eat, drink, or smoke within the crime scene - remove the gun's from the scene of any homicide or suicide when officer's life is not in jeopardy - move the deceased body in any way • this includes rolling the body over; remember this will contaminate any evidence located on the back of the body - if the subject is obviously deceased, discuss this with EMS to avoid disturbing potential evidence on the body of the deceased - do not call the medical examiner

arrival at the crime scene

- upon arrival at a crime scene the first responding police officer to a crime scene is responsible for: • 1) acquiring medical assistance for injured victims º medical personnel avoid disturbing evidence and approach the victim by an indirect route → need a description of what occurred to piece together the scene º integrity of the scene is SECONDARY after medical attention • 2) detaining any potential suspects or witnesses º statements are taken from victims, witnesses, and suspects º secure witnesses separately → NO collaboration or influence º under stress we don't remember everything → investigators have to fill in the blanks • 3) securing the crime scene to the greatest extent possible → take evidence furthest from the focal point and then extend an extra 50% distance to make sure you get as much evidence as possible º the boundary is sealed off, and guards are posted at the entry to the crime scene if needed ↳ ONLY one way in and one way out of the scene ↳ person at that point keeps a log of who enters and leaves º all civilians and unauthorized personnel are excluded from the crime scene ↳ ONLY CSI agent(s) are allowed in until complete overview of the scene, once done others are allowed in • 4) calling for any additional personnel needs such as other officers and/or forensic investigators º the personnel required depends upon the nature of the crime scene

casting material

- used on rough or irregular shaped objects - print is dusted with powder - a casting gel or silicon is applied to lift the latent - ex: door knob, textured paint, bottle or can

line search

- variation of the strip search, where multiple searchers follow a single strip in one direction, while on-line with each other • can easily get lost/ confused • use the resources of multiple sets of eyes - excellent for exterior scenes over rough terrain - usually requires supervisor(s) to maintain the direction and alignment of the involved searchers

video photography

- video is a functional supplement to crime scene documentation, but does not replace any documentation product - 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 results in abrupt motion and bad focus • unless in sunlight always use a video strobe, never use a flashlight to illuminate the scene - critical mistakes: • panning too quickly • not keeping the camera on an item long enough • inappropriate comments made in the audio track

sequencing for porous items

- visual - iodine/ Ruthenium Tetroxide (RTX) - ninhydrin → reacts with amino acids and creates a purple color - indanedione - physical developer or silver nitrate

sequencing for non-porous surfaces

- visual/ alternate light source (ALS) - cyanoacrylate - dye stain - powder

environmental factors

- what happens to the evidence between the times a latent print is deposited and the time it is recovered can greatly affect the processing outcome - placing firearms in holsters, in the waist-band of trousers, between car seats, and under mattresses, to give a few examples, may cause the latent prints to rub off - latent prints on items that are thrown from moving vehicles onto roadways, dusty fields, and into rapid-running rivers, etc., may also be obliterated - offenders known to wipe off the interior and exterior of items, thereby eliminating any chance of developing identifiable latent prints

direct light vs. oblique light

- when 3D evidence has to be photographed, directly lighting the evidence is actually counter productive to producing the best photograph possible - oblique lighting creates shadows, which makes it easier to see the 3D aspects of the pattern

reference points

- when measuring an outdoor scene, recommended reference points include: • power poles • light poles • the point where the sidewalk or driveway intersects with a street • the seams in a curb intersections - when measuring an indoor scene, the concept is the same as for outdoor scenes. common reference points include the corners of a room or the point where a doorway intersects with the floor - rectangular measurements only require two adjacent, perpendicular walls that create a right angle (the measurements, obviously, MUST intersect)

use of establishing photo

- where is this item in the scene? • the background itself might indicate a number of locations • need to identify the specific layout of where the evidence was found

cardinal rule #3 → keep the film plane parallel

- which angle of view is the best for the primary subject? often, having the film plane parallel to the main object is best - overall photographs may be photos of building facades or walls - keeping the film plane parallel in overall photographs eliminates many problems with • scale • focus • flash - diagonal shots may cause these problems - some well-known exceptions to this rule: • windows or mirrors • highly reflective subject • not enough room to get parallel - having the film plane parallel to the evidence is critical with close-ups of the subject. frequently, if the film plane is not parallel to the subject, the close-up cannot be used for comparison purposes

whorls

- whorls are divided into four groups • plain whorl • central pocket loop • double loop • accidental - a whorl pattern consists of a series of almost concentric circles. like tiny whirlpools - all whorl patterns have type lines and a minimum of two deltas

3D "sketches"

- with the on-set of technology (e.g. Total Station systems and CAD) detailed measurements from the scene can be used to create "virtual" scenes - this allows 3-dimensional perspectives from any position in the scene - this also allows the creation of "walk through" demonstrative evidence that shows the jury the scene