A criminalist is a person with a background in science, typically having at least a baccalaureate degree in an area such as chemistry, biology, forensic science, or criminalistics. Some criminalists have degrees in other, similarly related areas. Many criminalists have advanced degrees.
With the above scientific background and
additional training given by his/her employer (either a government or private
laboratory) a criminalist applies scientific methods and techniques to examine
and analyze evidentiary items and testifies in court as to his or her
findings. Please read below, under
criminalistics, for a more detailed description of what criminalists do.
The California Association of Criminalists (CAC) is a professional membership organization of forensic scientists founded in 1954 by sixteen members from various agencies throughout California. They met to exchange ideas, new testing methodologies and to share case histories. Since its inception, the CAC has expanded its membership throughout the United States and Europe. The CAC is the oldest established regional forensic science organization in America. CAC Members are employed in local, state and federal governmental agencies, as well as private companies and teaching institutions.
Today, there are many members representing an array of
forensic science specialties. They include criminalists, document examiners,
serologists, toxicologists, chemists, molecular biologists, firearm &
toolmark examiners and educators. CAC members are involved in national forensic
science organizations such as SWGDAM, SWGMAT, ASCLD, ASCLD-LAB, ASTM E-30, DAB,
ABC and AAFS. CAC membership provides an opportunity to be involved in the
professional activities that affect one's career, the profession of
criminalistics and the criminal justice system.
Criminalists provide
information to investigators about the caliber and type of
firearm used in a crime.
Scratches, or striation marks, are left on bullets by
the barrel of a pistol
or rifle. Once a firearm is recovered, these marks can
individualize a bullet
to a unique firearm to the exclusion of all other
firearms. Similarly,
tools used in crimes can leave striation and other marks
on surfaces. These marks
can be compared to the tool believed to have made
them. If the comparison
is a positive match, a tool may be individualized as
having made the mark to
the exclusion of all other tools. A computer database
of marks on cartridge
cases and bullets has been developed to link a particular
firearm to serial
crimes.
Trace evidence, frequently overlooked because
of its microscopic size, applies
microanalysis to fibers,
hair, soil, paint, glass, pollen, explosives, gunshot
residue, food, plastic
bags, and virtually anything involved in a crime. No
training exists that
will prepare the trace evidence analyst for every kind of
case that will cross
their workbench, as each case is fascinatingly unique. By
having a thorough
knowledge of the advantages and disadvantages of microscopic,
spectroscopic, and
chromatographic methods, the criminalist can meet the
analytical challenge of
each case.
In the mid 1980Ęs,
deoxyribonucleic acid (DNA) techniques began to be applied
to forensic cases. Any tissue
from the body carrying the genetic code of DNA
may be used to compare
to a standard. This allows blood to be associated
uniquely to a single
individual. Databases of DNA profiles are being compiled
to aid in identifying
criminals and have already been used to solve cases many
years old, where samples
were properly preserved and reanalyzed. In some cases
innocent persons have
even been released from prison based on the reanalysis.
The criminalist uses a
battery of analytical tools and their knowledge of
chemistry to identify
controlled substances in powders, pills and liquids and
body fluids. A
criminalist may be called to a clandestine laboratory by
investigators, where
illegal drugs are produced. Criminalists are frequently
responsible for
maintaining breath alcohol analysis instruments and training of
the laboratory
technicians and police officers who run the tests on those
suspected of driving
under the influence. Sometimes no controlled substance is
present and sometimes
more than one kind of drug can be detected in a sample.
Criminalistics is one of
many divisions in the field of forensic science.
Forensic science
includes forensic pathology, odontology, entomology,
engineering,
criminology, and other disciplines. All of these are specialized
sections in forensic
science. Criminalists use techniques learned in chemistry,
molecular biology,
geology, and other scientific disciplines to investigate and
solve crimes.
Criminalistics should not be confused with the field of
criminology.
Criminologists are sociologists, psychologists, and others who
study the causes and
effects of crime on society.
For the criminalist,
crime scene investigation involves the recognition,
documentation,
collection, preservation, and interpretation of physical
evidence which may be as
big as a truck or as small as a diatom or pollen
grain. Recognition of
items out of place, articles improperly located or items
added to the crime scene
are an important part of crime scene processing. The
criminalist collects,
preserves, and makes interpretations about the evidence
and their relation to
the series of events resulting at the crime scene.
The criminalist brings
evidence back to the laboratory where examinations will
be conducted. Interpretations
are made about the relevance of a particular item
from the crime scene by
associating particular items of evidence to specific
sources and
reconstructing the crime scene. This means not only associating a
suspect with a scene but
also the telling of a story about what transpired
before, during and after
the crime.
The criminalist must
draw on a wide spectrum of scientific knowledge including
chemistry, biology,
genetics, molecular biology, physics, statistics and a
working knowledge of
civil and criminal law. Applying this knowledge,
criminalist will
associate and identify evidence, interpret the results,
reconstruct the crime
scene, and write a report summarizing the findings.
Finally, the criminalist
testifies in courts of law, teaching the judge and
jury about the
conclusions reached in the laboratory.
The end of the journey
is the court room where testimony of the crime scene
work, laboratory
analysis, the conclusions on the report and interpretation of
the evidence will be
presented and questioned. The criminalist tells the truth
in an unbiased manner,
educating the jurors about the techniques that were
used, the results
obtained and interpretations derived from those conclusions.
The criminalist must
answer the question posed so that their answer is not
misleading the jurors.
If the question posed requires a yes or no answer but an
explanation is needed to
explain the yes or no answer, they are obligated to
give an explanation.
Professionally, the criminalist does not care whether the
defendant is found
guilty or not guilty. Presentation of the evidence in a fair
and unbiased manner and
telling the truth are the primary obligations of the
criminalist.