Forensic Lab Refelections

Over the creation of this blog my class participated in multiple forensic based labs in order to further comprehend the material as well as better understand non ideal instances.

Finger Prints

In class we practiced fingerprint identification. First off to practice creating prints we treated the pads of our fingers with blue ink and pressed them onto the chart below.

The blue ink left behind easily identifiable prints which made discerning characterisitcs of them simple. However since in most cases criminals do not leave prints with blue ink we were then assigned to lift our prints off a glass jar. To do this we cleaned the bottom of a jar to make print identification easier. After placing our print on the jar we applied in crushed graphite as a black powder with a fine brush. Once the print was identified tape was used to lift the graphite imprint onto a scrap of white paper.

Hair Analysis

For criminal's it is nearly impossible to commit a crime without leaving behind some kind of fiber. In lab we analyzed the common types of fiber that would be found at a crime scene for color, tip condition and an distinguishing features. The fibers we analyzed included;

• Caucasian: The hair had multiple visible pockets in it
• Dog: The Medula was much more distinguished, however the hair sample was frayed
• Cotton: Fibers formed a twisted pattern
• Synthetic: A solid, smooth fiber
• Asian: It had a tanish yellow hue, however in appearence it was similar to caucasion, except more frayed
• Cat: looks similar to synthetic fiber
• African American: The core seems less dense but the overall hair was darker
• Color Treated wool: Incredibly twisted but other wise smooth
• Nylon: Formed a web like pattern but ends were split.
• Blue silk: Formed a crochete pattern

Witness Experiment

Often when a crime is commited there is somesort of witness, these people can be used by forensic scientists for identifiying a criminal. In our experiment we took a common magazine and cut out various individual's hair eyes, nose, and mouth. The task was to then piece together an individual from the mix of parts similar to the way scientists must piece together an 'image' of a criminal from I-witness reports. What was taken from this is an ability to create an image that could be used for finding a criminal.

Lipstick Analysis

Somtimes in crime cases stains of lipstick can be found, scientists soon relized that these prints were just as unique as fingerprints and thus lipstick analysis was born. In class everyone had to apply lipstick and make a print on a scrap of paper. After which we analyzed for any distinct features such as valleys and special creases.



Handwriting

One class we were assigned to write a fake check along with each of our groupmates. We proceeded to rip them to pieces and mix them up with our group. After which we worked together using the 12 handwriting components to identifiy our own check and piece it together.

Foot Printing

We broke off into groups each with a bin of dirt. Once this happened each memeber of the group took a turn pressing their right foot into the bin to leave behind a foot print after which we began analysis. The analysis regarded particular details such as different areas in the shoe that are heavily worn; this information can be used to identify individuals as everyone walks a different way. When prints are left behind scientists can obtain infomation such as the footwear manufacturer, model and shoe size to help profile witness and suspects.

This right foot print has a worn away inside curve. This can be seen as the circular markings that are in the circle become less prevalent towards the left of the foot. (the spoon in the picture was used for outlining the print)

Though footprints are always left behind they may not be in perfect condition, however information can still be obtained from only partial foot prints. It the creator of the footprint was obviously wearing high heels, this could be used to narrow down a suspect list to females (in most cases).

My personal footprint, as stated forensic scientists can identify the company that produced a shoe in order to hunt down a criminal. In this case the manufactuor can easily be identified by the logo in the heel as oceanpacific. From here law enforcement can trace who owns a pair produced by this company adding to useable evidence.

Drug Analysis

In this lab our teacher created compounds that simulated the chemical properties of common drugs. Students were to mix these substances with roughly 25ml of water (small samples were put onto a dish in order to save resources). Once this was done the students tested PH levels (as this can be used to determine certain types of drugs). Then a common test police officers use is reagents that turn blue in cocaine, or yellow in L.S.D. this knowledge is important to a forensic scientist as it could be used as drugs may be the cause of death such as an overdose.

(The pink liquid was one that didn't react)

Poison

A common method of killing, poison can be multiple common compounds. In our class students were tasked with determing weather certain substances were poisonous via certain indicators. The poisons that were tested for include, cyanide, iodine, heavy metal poisoning sugar (if one is diabetic), household ammonia and asprin (in the case of an overdose). Students also were required to research poison for certian points of interest (such as the definition of a poision, how it can be useful forensic scientists to know this). In the end we learned that poision can be used to trace criminals as it can be traced which of the suspects would have access to the used poison.

Creating a Profile

Using the skills obtained from previous labs a group of four of us were tasked with a common job that forensic scientists must do frequently. That is creating a profile from the information given. As a group we were each given a hair sample a torn up note, a set of fingerprints and a lipstick sample. Through group analysis we recorded all the information we could discern from the clues and then thought of further information required to identify a criminal.