CRIME SCENE INVESTIGATION
CRIME
The Dictionary defines "crime" as: An act committed
or omitted in violation of law forbidding or commanding it, and for which
punishment is imposed upon conviction.
The basic qualities of a good crime scene investigator are intuition
and an eye for what needs to be done. Crime scene investigation is characterized
by three essential conditions for success; organization, thoroughness and
caution.
Objectives of crime scene investigation are as follows:
- RECONSTRUCT INCIDENT
- ASCERTAIN SEQUENCE OF EVENTS
- DETERMINE MODE OF OPERATION
- DISCLOSE MOTIVE
- DETERMINE PROPERTY TAKEN
- FIND OUT ALL THAT CRIMINAL HAD DONE
- RECOVER PHYSICAL EVIDENCE
Remember: Mistakes made during the investigation may never be
rectified. See to it that reporters do not learn of specific clues or conditions
at the crime scene that may be essential to the solution of the crime.
Processing the crime scene consists of careful examination,
note taking, sketching, photography, and collecting of evidence. The order
of the various phases of processing a scene must be decided on a case by
case basis. Evidence and information of a fragile nature should be collected
before material that is less likely to be lost or destroyed. Let the detailed
examination of the body wait until basic examination of the scene has been
completed.
THIS SECTION WILL NOT BE IN ANY TYPE OF ORGANIZED ORDER. I WILL
JUST ADD MY THOUGHTS AND IDEAS AS I CAN GET TO THEM. SO YOU WILL NEED TO
CHECK BACK FOR UPDATED INFORMATION.
POST MORTEM LIVIDITY
(LIVER MORTIS) Is the medical term describing the bluish-purple
color that developes after death in the undermost parts of the body-i.e.,
those that have been facing downward. A living person's blood circulates
under pressure from the heart muscle, but a dead person's pressure drops
to zero and gravity causes the blood cells to sink to the bottom of the
circulatory pipelines. Lividity can be evident within 30 min. of death
and will remain where started, even if the body is subsequently moved.
Lividity does not form on parts of the body exposed to pressure. At 24
hours the lividity becomes "fixed" meaning the area will not
llanch with pressure applied. If signs of lividity can be seen on the top
and side surfaces of the body, the inference can be drawn that it was moved
after death.
RIGOR MORTIS
(RIGIDITY) Is the stiffening of the body after death, and is
the result of chemical changes within muscle tissue ( lack of ATP). Evident
at first in the small muscles of the hand and jaw (in two to four hours),
it becomes more obvious in the larger muscles (in four to six hours),
and is fully developed in twelve hours where it remains until postmortem
decomposition begins.
DECOMPOSITION
(PUTREFACTION) AUTOLYSIS Is the softening and liquidfication
of tissue. Bacterial breakdown begins at death with a green or red color
on skin and continues until the body is completely decomposed exposing
the bones. Decomposition may be excellerated by weather conditions or animal
life.
AUTOEROTIC ASPHYXIA
A form of sexual gratification where the victim uses intermittent
oxygen deprivation to heighten sexual stimulation. Often, controlled strangulation
is the preferred method. However, a slight miscalculation or loss of consciousness
kills the victim. This form of death is considered accidental.
HESITATION MARKS
In a suicide attempt, the victim will usually make several superficial
incised wounds before making the fatal wound. They often lay adjacent to,
underlying, or in continuation with the fatally inflicted wound. They are
seen on the inside surface of the wrist, the elbow or the neck.
IMMERSION BURNS
These are burns that are usually seen in child abuse cases and
are caused by dipping the victim into a hot liquid. There will generally
be immersion lines around the victims limbs and often will be seen are
defense or "spared" spots on the victim. These are area's where
the victim flexed his body to to avoid being touched by the scalding liquid.
PETECHIAL HEMORRHAGES
These are minute pinpoint spots on the skin, sclera, or mucous
membranes caused by small blood vessels bursting beneath the epidermis.
It is often associated with asphyxia deaths.
SKIN SLIPPAGE
During decomposition by putrefaction, the skin breaks down and
begins to slough off in large pieces. It often resembles the blistering
of skin found in burns.
TORN FRENULUM
The frenulum is the piece of skin flap located under the upper
lip and attached to the upper gum. It is very difficult to damage this
are and is often found as an injury in child abuse cases. A few ways that
the frenulum may become injured is by forcing an item into the mouth, punching
or hitting the mouth, or by struggling while being smothered.
