Det/Lt. Timothy F. Hahn,
SCSA (Ret) -
tim_hahn@msn.com
What is Reconstruction?
“Crime scene reconstruction is the
art of interpreting the available
information to determine what
actions were taken by both suspects
and victims at the scene of a
crime.”
Crime Scene Reconstruction falls
more into the category of an art
rather than a science. This is due
to the fact that multiple
disciplines are used during a
reconstruction. A reconstruction
artist must not only be well versed
at working crime scenes and
investigating those crimes, but must
also have additional training in
blood spatter interpretation,
firearms trajectory analysis, wound
ballistics, wound analysis and much
more. Any artist worth his or her
salt in this field also has numerous
contacts that can be consulted at
various times.
Read the full article
here
Photographic Techniques for
the Laser or Alternate Light
Source
by
Hayden
B. Baldwin
As crime scene technicians we are
accustom to photographing the crime
scenes and using forensic
photography techniques to capture on
film the fingerprints, footwear
patterns, toolmarks, bite marks and
blood spatter patterns that are
found at the various crime scenes.
Why then do we have a problem
photographing items with the laser
or ALS source? We think of the laser
or ALS as another light source, such
as the photo bulb or electronic
flash, however it is not the same
photographic technique.
Read the full article
here
Slave Flash Photography
Using a Slave Flash with the
Epson PhotoPC
by
Hayden
B. Baldwin
The Epson PhotoPC digital camera has
a built-in flash sufficient for
distance of 10 feet or less. This
flash is similar to flashes built-in
on most point and shoot type
cameras. Their flash range is
limited. However, with a slave
flash, the distance can be increased
to 18, 25, even 40 feet...depending
on the flash used as a slave flash.
A slave flash is ANY photographic
flash attached to a slave unit. A
slave unit has a sensor built into
the unit that is flash sensitive.
The slave unit can "sense" when a
photographic flash has been fired.
The slave unit then closes its
circuit and activates whatever flash
is attached to it. Most are so
sensitive that they can be activated
100 feet away in full sunlight!
Read the full article
here
Oblique Lighting with the
ALS
by
Hayden
B. Baldwin
Photographing a footwear impression
in dust is sometimes difficult,
especially if the dustprint is on a
highly reflective surface, such as a
gelatin lift or mylar from an
electrostatic dustprint lift. Either
reflective surface will cause glare
back into the camera from the light
source. However by using the ALS, a
beam of light can be positioned so
the light is parallel and just above
the reflective surface. This
lighting technique has proven
successful in photographing these
difficult surfaces. No camera
reflections, no light flares, no hot
spots - just even lighting for a
photograph suitable for comparison
to the suspected footwear.
Read the full article
here
Night Photography timed
exposures
by
Hayden
B. Baldwin
This article is demonstrating a
series of photographs taken at
different exposure times
Read the full article
here
Creating panorama photos in
crime scenes using your
current camera equipment
by
Hayden
B. Baldwin
Panoramas in crime scene work has
always been a useful tool in
depicting the area near the crime
scene or even in the crime scene. In
the past the equipment required to
create and shoot panoramas was cost
prohibitive for most police
agencies. Now panoramas can be made
with your current camera equipment.
Nothing new to buy and the software
is available free from various
sources. Panoramas are nothing more
than a series of photos taken so the
image is overlapped from one image
to the next. Many of the newer
imaging programs have this feature.
Read the full article
here
A sample of Cross
polarization with linear
lighting
by
Hayden
B. Baldwin
A linear polarizing sheet was used
as a filter over the light source
and a circular polarizer used on the
camera.
Read the full article
here
by
Hayden
B. Baldwin
Macro photography requires a greater
DOF to ensure the fingerprint or
mark on curved objects are in focus.
Read the full article
here
Photographing and casting of
three-dimensional tracks
by
Ernest
D. Hamm
Track evidence at the scenes of
crime is probably the most
overlooked and under collected type
of evidence than any other form of
physical evidence encountered by a
crime scene investigator. However,
it is probably the easiest to
recognize and, with minimum effort,
to document and recover. Man has
been using tracks as a form of human
and animal identification for
hundreds and hundreds of years.
Modern man almost automatically
assumes their presence at a scene.
Tracks have been used and accepted
as a standard for establishing one's
presence in a place, evidence that
"he was there". Even though it has
been widely under used over the
years, track evidence is probably
the oldest form of criminalistics
that was used in an investigation.
Read the full article
here
by
Hayden
B. Baldwin
It can be very difficult to describe
the layout of an area, building or
even a single room to someone.
However, with the use of a sketch it
becomes much easier to describe and
understand the floor plan. The
prosecuting attorney may use a
sketch to demonstrate to the jury
the layout of the building. They may
ask the witness to indicate on the
diagram exactly where he was when he
heard the gunshot. This method of
demonstrative evidence can far
easier explain to the jury what
happened and where it happened. The
rough sketch that was completed by
the crime scene investigator is for
the preparation of a finished
diagram to be used in a court
presentation. The investigator may
draw a rough sketch of a scene to
aid in their investigation by
recording certain important facts
that are difficult to put into
words.
Read the full article
here
Crime Scene Interpretation
by
Hayden
B. Baldwin
The reconstruction of crime scenes
is a miss nomenclature. You are in
reality interpreting the information
that you find by examining and
processing the scene for evidence.
This evidence will then permit you
to make factual statements in
regards to your findings. For
instance, examining a footwear
impression left at a scene you will
be able to determine what direction
the person was walking when that
impression was made. Therefore you
are interpreting the information you
discovered to develop a factual
reconstruction. In other words you
are placing your interpretations in
a logical order to reconstruct what
has taken place in the crime scene.
This will apply to all crime scenes
that are left intact and are not
disturb by the victims, paramedics
or police officers. Without this
"virgin" crime scene the
interpretation could be altered and
may not be as it was when the
suspect(s) were there. Never, never
assume or guess at the
reconstruction without all the facts
from the interpretation.
Read the full article
here
Attending a crime scene - A FLOs
perspective
by Kalisa Hadji
During the investigation of major
crimes, different departments in law
enforcement are required to aid in
the investigation. Forensic
Laboratory Officers (FLO) (working
in a fingerprint development lab),
in my department (Scientific Support
Unit) we are not required to attend
every crime scene for the
investigation unless the incident is
a major crime. The main reason for
this is due to Health and Safety
issues risen from the chemicals used
for the development of latent finger
marks
Read the full article
here
