Document Sample
Forensics-introduction Powered By Docstoc
					                                  Fingerprinting Forensics
        There are many types of chemistry including several used in life saving studies.
Forensics is one of them. Forensics is the study of evidence found at a crime scene and
that is used in courts of law.(1) Forensics helps police officers and crime scene
investigators to find criminals and to effectively convict these criminals in courts.(1) One
very unique area of forensics is fingerprinting. First used to sign letters and documents in
the time of Christ(3) and evolving into effective human identifiers in 1880, fingerprints
are now electronically submitted and used in criminal trials.(2) Fingerprints are found
everywhere and no two person’s prints are identical.(3) Plus, they never go away. If the
fingertip skin is removed the same ridge pattern will reform on the finger as it heals. (8)
All investigators know this and use this knowledge everyday. For a quick and easy search
for print clues at a crime scene, investigators sometimes use a superglue fuming method.
(4) This method was created in 1977 by Masato Soba.(5) It is an easy way to see if the
prints of a possible perpetrator can be found on pieces of evidence.(3) Lots of chemistry
goes into producing fingerprints and not a lot of people know that. Fingerprints and
forensics are a very important part of chemistry and our society today.
        Forensics is a study of chemistry in that many chemicals and reactions are used as
a part of it. Fingerprinting, although it is a small area of forensics, is full of chemistry. A
finger has many tiny sweat pores.(6) These pores are found on the ridges of skin that
make up a fingerprint.(6) When a person touches something, the pores on the finger leave
behind sweat and oil made up of water, salts, sugars, ammonia, and urea.(6, 7) This oil is
what makes up a fingerprint and is called a latent print, meaning that it is invisible.(6)
These prints can, then, be lifted, fumed, or seen using argon lasers.(6) That is ultimately
where the chemistry begins. To lift a print investigators use elements such as aluminum,
carbon black, and titanium powder.(6) These fine powders stick to the print and can be
lifted using sticky tape.(6) Another way to find a fingerprint and send it to a lab is to use
cyanoacrylate vapor.(6) This vapor combines with the amino acids in the print to make it
hard and white.(6) Now that the print is visible it can be photographed for evidence.(6)
Iodine fuming and a process of ninhydrin dipping use the same concept.(6) These
substances bind and react with the oils and salts in the fingerprint to make it visible.(6)
The compound silver nitrate is very helpful, as well. When the sodium chloride present in
the print reacts with silver nitrate, sliver chloride is made.(6) The silver chloride,
although it has no color, becomes visible under ultra violet lighting.(6) All of these
methods of revealing latent fingerprints are affective. One may not now that chemistry is
essential to fingerprinting, but it is a necessary asset at crime scenes and in courts.
       Our group thought it would be neat to put our forensic knowledge to the test. We
found an activity to do called superglue fuming. This is a lab used to reveal latent
fingerprints on hard surfaces.(6) First we need to have a card board box and make a small
tray out of aluminum foil.(4) Then we have to put a little amount of superglue on this tray
and put it on a heat source, such as a coffee cup warmer, in the box along with the
evidence, a test print, and a glass of water.(4) Closing the box and turning on the heat
source is the next step.(4) Then, after waiting for about ten minutes we can open the box
and view the evidence which should be covered in a white residue.(4) If the object is not
covered well, we should close the box for a few more minutes.(4) Finally, once prints are
visible, our evidence is ready for analysis.(4) Doing a hands- on activity just like
investigators is interesting and gives us a taste of the work that professionals do.
Forensics is complicated, but it is fun at the same time.
       Forensics, especially fingerprinting, can be very important. Finding out that
fingerprints are made of sweat and oil that comes from tiny pores on ones finger tips was
interesting. (6) Also, that no two people have identical prints and that they are one of the
best identifiers was intriguing. (3) What was the most fun, though, was the fuming lab.
Being able to find latent prints on our own in the classroom happened to be our favorite
part of the project. Superglue fuming is done by investigators as a pre-official or
permanent way to find prints at the crime site. (4) This research left us pondering how
many fingerprints are in the U.S.’s computerized system? How many criminal court cases
have relied on fingerprints to convict a perpetrator? Plus, is there any other part of a
person’s body capable of the same kind of identification? The community is also affected
by this type of forensics. We are protected from criminals, can make sure we are
convicting the right criminals, and this particular forensics provides many with jobs, such
as, investigators, policemen, fingerprint experts, medical examiners, and crime scene
photographers.(9) There are a couple different kinds of fingerprints, but latent prints are
by far the most challenging to find and protect. Human fingers are essential to normal life
and most people do not even pay attention to the evidence they leave behind by touching
objects. Right now you are leaving a latent print on this paper, the pen in your hand, and
in a moment, the desk you will touch. What if the room you are in becomes a crime
scene? You could be a possible perpetrator in the eyes of an investigator, all because your
prints have been left behind. Fingerprints are amazing things and come in handy quite
1. Oracle Think Quest, Education Foundation. What is forensics?. (accessed March 19, 2010).

2. Aggrawal ,Prof. Anil , Munroe B.Sc., Richard. History of Forensic Science: History of
   Crime. (March 2, 2010).

3. Pierce County Sheriff. Forensics History. (March 28, 2010).

4. German, Ed, CLPE,FFS. Finding and Processing Latent Prints. (March 19, 2010).Forensic

5. Forensic Science Timeline. (March 19, 2010).

6. Investigations. Fingerprinting. (March 28,

7. New World Encyclopedia. Sweat.
   (March 29, 2010).

8. Forensic Science-Fingerprints.
   Fingerprints.html (March 28, 2010).

9. What is Forensics?. (March
   19, 2010).

Shared By: