investigations and psych profiling warning extremely graphic material specially prepared for...

Investigations and Psych Profiling

WARNING

EXTREMELY GRAPHIC MATERIAL

Specially prepared for students of Dr. P. Kaplan CJ430

Week 4

Criminal InvestigationsPostmortem Change

POSTMORTEM CHANGE: LIVOR MORTIS

After death, the blood pools in the small blood

vessels of the skin, producing a deep purple

color in dependent (lower) areas of the body.

In areas where the body is in physical contact with the

ground, the skin blood vessels are closed by the

weight of the body, resulting in blanching

(pale white areas) which indicates how the body was

positioned.

Criminal Investigations


When livor mortis forms, blood pools to the lowest

points in the body as positioned due to gravity.



Livor mortis begins to form immediately upon

death, as blood collects in vessels (venous stasis). Typically, livor is

not apparent for at least 30minutes to the trained investigator or

up to about 2 hours to a novice.

Over the first ~12 hours after death, livor becomes more and more

prominent.


POSTMORTEM CHANGE: TARDIEU SPOTS

An important distinction to be made is Tardieu

spots in the area of the head and neck (arrows) from

petechial hemorrhages in the skin resulting from

strangulation.


POSTMORTEM CHANGE: TARDIEU SPOTSAs the process of

decomposition proceeds, theblood vessels in the skin continue to break down.

As this happens, more blood leaks out into the skin.


POSTMORTEM CHANGE: RIGOR MORTIS

Rigor forms as the body is positioned after death

and becomes more developed over the next several

hours until it becomes full or fixed (i.e. no more

rigor can form).


DECOMPOSITION: ENVIRONMENTThe environment greatly affects the condition of the body after death. When the temperature is high and/or the environment humid, decomposition occurs more rapidly (blue arrow). When the environment is cool and/or the humidity is low, decomposition is slowed (yellow arrow). Here, both extremes are demonstrated in the same case. Both died at the same time. The male was

in the hot, humid attic and the female was in the cool, dry basement.


DECOMPOSITION: MUMMIFICATION

In hot, dry environments, the skin tends to lose

moisture. The result is drying of the skin to a tough,

leathery state. Here, the body was clothed in a T-shirt

and panties at the scene



In an open-air environment with a breeze, direct

sunlight tends to dry the skin while wind pushes the

moisture away, allowing further drying

(mummification) to continue. The exposed areas of

the back.

INAPPROPRIATEDECOMPOSITION. In the latter,

carnivores areattracted to the exposed blood and

body fluids at aninjury site and feed there in

preference to otherareas.



Even in cases where the rest of the body undergoes

a “wet” or bloated decomposition, the hands

oftenhave drying of the fingers

(arrow). The skinbecomes leathery and hard.

The drying retardsdecomposition, preserving

fingerprints.


DECOMPOSITION: VENOUS MARBLING

In hot, moist environments the body undergoes two

concurrent processes:

Autolysis is the steriledigestion of the body by the natural

enzymesalready present within the cells.

Putrefaction is thebreakdown of the body by bacteria.

As the bacteriadegrade the tissues, hydrogen

sulfide gas formswithin the blood vessels, resulting

in irregular darkblue-black lines (yellow arrows).

SKIN SLIPPAGE.


DECOMPOSITION: SKIN SLIP

As the body undergoes putrefaction, clear blood

tingedfluid-filled blisters (yellow

arrows) form onthe skin surface, lifting the superficial layers of

theskin surface up.


With even minor surface trauma

(such as friction) the blisters may pop, removing the

superficial skin layers (red arrow) and exposing thedeeper skin layers (white

arrow). With time, theexposed skin layers dry with a

dull yellow surfaceand might be confused with a

pre-mortem abrasion.


DECOMPOSITION: BLOATINGThe swelling of the body produced by bacterial action during putrefaction can be extreme. The investigator should be cautious to not over interpret some findings,

such as tearing of the clothing due to bloating (yellow arrow), as representing trauma. Note also the skin slip caused by rubbing against

the pants fabric (red arrows).


DECOMPOSITION: BLOATINGSwelling is often prominent in the face in

putrefaction, significantly hindering a visual identification.


DECOMPOSITION: PURGE FLUID

Purge fluid (yellow arrow) may soil the

undergarments, if worn. In many sudden deathcases, there may be

perimortem incontinence of feces and urine.

Criminal InvestigationsDECOMPOSITION:

EXHUMATIONEven though embalming

and burial slow thedecomposition process, the

changes still occur – at amuch slower rate. Here, the

subject has been buriedin a dry casket for five

years. The skin surfaces aredried and leathery

(mummified). Even aftercleaning, colonies of fungus

remain (red arrows). Inthis case, the body was autopsied prior to the

original burial (incision = blue arrows).


THERAPY: ARTIFACTOften when a subject is

transported to theemergency room,

therapeutic artifacts areintroduced. A common

finding is squared linearabrasions (yellow arrow) on

the front and left sideof the chest.


THERAPY: ARTIFACTWhen a defibrillator is

used, plastic sheets (bluearrow) are used to ensure

good electrical contact.Electrocardiograph leads

(white arrow) are alsooften present. These are

designed to detect naturalheart activity and as a

result do not have associated skin lesions. All such coverings should be

removed to allow inspection of the entire

body surface for injuries.


DECOMPOSITION: INSECTSProtected moist areas (arrows) are favored sites for the laying of eggs. These would include the eyes, nose, mouth, and axillae (armpits). The presence of only fly eggs, without adult or larval

(maggot) forms suggest an interval of more than several hours but less than a day. The deposition and hatching of eggs depends on the species of fly. All available information should be considered in the estimation of a post-mortem interval; no single factor should be unconditionally considered

“the most important.” Caution is the best advice in the estimation of time since death.

Criminal InvestigationsDECOMPOSITION: INSECTSThis body was found with the

pants about the ankles (yellow arrow) and the genitalia was covered by feeding larvae

(maggots = blue arrow). Although the circumstances of the body’s discovery were suspicious, this residence was one known for

prostitution in exchange for crack cocaine. The larvae had eaten

most of the genital area, obscuring identification of any possible pre-mortem trauma.

The remainder of the body had no identified trauma. Based on these facts, the cause of death was left undetermined. The insect activity suggests a postmortem interval of approximately a couple of days –

this is unique to this area and may represent a different interval than other areas and/or with other

fly species.

Criminal InvestigationsDECOMPOSITION:

INSECTSAdult blow flies (yellow

arrows) with larvae(maggots = blue arrow) at the area of the nose. Thissuggests an interval of a day or two. Samples of

both adult and larval forms should be collected as

described above (i.e. living and heat-killed samples

of both)


DECOMPOSITION: POSITIONCertain properties are consistent in all death cases. When insects

feed on a body, they begin at areas of easily accessed food –

this could be either typicalpurge fluid or blood from a pre-

mortem wound.


DECOMPOSITION: ANT BITES Multiple

insects may involve the body simultaneously. Fly eggs (blue arrow)

and larvae are attracted to orifices and

bloody fluid, such as purge. Ants are

attracted to exposed areas and, in particular,

to blood on the body surface. The result is

superficial orange-pink to yellow irregular

(geographic) abrasions


EXPOSURE Exposed areas decompose more rapidly than non-exposed areas. Bodies in water decompose at a rate roughly 4-8 times slower than those on land, dependent on the

temperature and other environmental conditions. In this case, the body was in a river with the head, right arm, and upper chest exposed; these areas show extreme decomposition with

skeletonization (arrows). The remaining (submerged) body is relatively preserved.


DECOMPOSITION: IDENTIFICATIONPersonal items can be used for a circumstantial ID.

These might include jewelry, watches, wallets, papers, fingernail polish (arrow), clothing, etc.


DECOMPOSITION: IDENTIFICATION Dental x-rays and

records offer an easy form of scientific identification. Here, the

pattern of the cavities (yellow arrows) and the different age (blue

and white arrows) fillings (amalgams) allows a definitive ID.

All identifications require a presumptive identity against which to

compare the unknown decedent.

Without a presumptive ID, a scientific ID cannot be made.


DECOMPOSITION: INJURY The decomposed body here has an entry gunshot wound (yellow arrow) to the forehead. Decomposition obscures

determination of the range of fire based on the overall gross appearance of the wound. After cleaning, the range was

still not readily discernible. Microscopic examination of the edge of the entry revealed the presence of soot and

gunpowder particles.

Even with the decomposition, the typical “raccoon eyes” hemorrhage

(blue arrow) from fractures of the orbital plates over the eyes is readily apparent.


SHARP FORCE: KNIFE MEASUREMENTS Suspect weapons should be measured to see if they have concordance with the wound(s). The blade length (yellow arrow) correlates to the wound depth (wound track). The blade width (blue arrow) correlates to the wound length. The blade

thickness (below) correlates to the wound width. The small unsharp portion of the blade (white arrow) is the RICASSO. Although these blades are serrated, there is no way, unless the blade passes across the skin surface, to determine if a serrated or regular blade caused a wound.


SHARP FORCE: KNIFE MEASUREMENTS The blade thickness (red arrow) corresponds to the wound width. This is the only wound measurement that is not highly variable, yet it is seldom recorded.


SHARP FORCE: STAB WOUND Typical stab wound

– the penetration into the body is longer than the

length of the wound (yellow arrow) on the body surface.

This wound has a single sharp edge (blue arrow) and

a single blunt edge (white arrow). In addition, the adjacent abrasion (red

arrow) is a HILT MARK and corresponds to the edge of the HILT (handle = black

arrow).


SHARP FORCE: INCISION The wound length (yellow arrow) is longer than the wound penetration into the body. The wound width (blue arrow) is of very little help, due to retraction of skin by elastic tissue. The edges are clean-cut as opposed to a laceration where tissues (nerves and blood vessels) BRIDGE (extend across the wound from one side to the other) the wound base. The edges (red arrow) are purple, indicating bleeding occurred. Thus the subject was alive when this wound was inflicted.

Criminal InvestigationsSHARP FORCE:

STAB and INCISIONS

Here, both stab (yellow arrow)

and incised (blue arrows) wounds

are present. Often, single sharp force

injuries are not immediately

lethal; thus there may be

movement of the victim, the

assailant, the blade, or any

combination. The adjacent bruising

(red arrows) indicates the

victim was alive for all these

injuries.

Criminal InvestigationsSHARP FORCE: BLADE

Occasionally, the blade

(yellow arrow) or a portion thereof will

break off within the body. This

can be very helpful if a

suspect weapon is found

because a TOOLMARK

ANALYSIS can be performed, matching the

portion of blade to the specific

weapon.


SHARP FORCE: STAB and INCISION Stab wound (yellow arrow) with trailing incised wound (blue arrow). The latter occurred as the sharp knife edge was dragged across the skin surface, either on penetration or on removal of the blade from the body. As can be imagined, the blade here was at an acute angle to the skin surface (see below). As such, the length of this wound may not correlate to the blade width. The blade thickness (correlating to the wound width) would remain constant.


SHARP FORCE: ANGLED/PARTIAL ENTRY

If the blade does not penetrate to the full depth, the wound may have varying lengths caused by the same blade. Here, the yellow lines represent varying depths of penetration. Likewise, at varying angles (blue lines), the same blade may cause

different wound lengths.


SHARP FORCE: INCISION Six different wounds all

caused by the same knife, demonstrating the marked variation in the appearance of wounds caused by sharp

weapons. In particular, incisions (as here) provide minimal to no information about the weapon used to

inflict them. Virtually any kind of sharp edge (knife, razor blade, broken glass, etc.)

could cause similar wounds to these.

Criminal InvestigationsSHARP FORCE: POSTMORTEM

Relatively superficial incision, penetrating to the soft tissues (blue arrow) under the skin. Here, the tissues are yellow, indicating that

the victim had negligible or no blood pressure

when these two wounds were inflicted. Both were

caused by the same weapon


SHARP FORCE: GAPING WOUNDS Single stab wound (yellow arrow) to chest, penetrating heart. The organs, and especially bone, are less elastic than skin and

thus may give more accurate approximations of the knife’s width and thickness. The motion associated with the beating of the heart may cause irregularities of the

wound.

Criminal InvestigationsSHARP FORCE: DOG-EAR

Single stab to chest, over heart. Note the gaping

wound (yellow arrow). When re-approximated, the blunt

edge (blue arrow) is apparent. In addition an adjacent abrasion (red

arrow), representing a HILT MARK is apparent, indicating

the blade penetrated to its maximal depth. The large,

oblique segment (white arrows) extending from the

stab is a DOG-EAR and indicates movement

(twisting) of the blade relative to the victim.


OVERKILL Multiple wounds, far in

excess of those required to kill are

termed overkill. Such cases, particularly if to

sexually significant areas (genitalia,

breasts, buttocks, neck, face, etc.), suggest a sexual element may be

involved in the crime. Several broad

categories of overkill cases include: sexual

sadist (lust killing), intimate relationship

(spouse, partner, family, homosexual relationship, etc.),

stimulant drugs, and psychiatric condition (esp. schizophrenia).

END SESSION 2 Criminal Investigations

SHARP FORCE: CHOP WOUND (Boat Propeller)

Chop wounds are a cross between sharp and blunt force wounds – a sharp

wound with a dull edge (i.e. propeller, machete, etc.). The edges are relatively

sharp and may have marginal abrasion. The parallel series of such

injuries (yellow arrows) is characteristic of a propeller.


DECAPITATION In this case of overkill (see pages 38 top and 44 top), the decedent sustained some 35

sharp force wounds. Here, the neck was cut into the spine, nearly severing the head.

Such extreme wounds suggest a particular

aggressive and forceful overkill attack.


That was a quick introduction –

Any questions?

investigations and psych profiling warning extremely graphic material specially prepared for...

Documents

body fluids

skin blood vessels

body undergoesa wet

blood pools

exposed blood

blood collects

blood leaks

livor mortisafter death