The Fields of Forensic Science

Over the years, new technology has developed and grown into something monumental. Forensic science has also grown with those technologies and uses them to this day. Forensic science first started by simply using a magnifying glass to analyze evidence, to nowadays using all sorts of chambers and processing stations to maximize the exactness of the evidence collected. The reason I chose this topic is because I have a passion for the criminal justice system. I believe that the criminal justice system plays a crucial part in society today and will continue to grow and have a huge impact on the world in the future. I am deciding to lean towards the forensics side of the criminal justice system mainly working in the blood spatter field. I have always been into math and science and growing up to become a scientist is a dream of mine. A Forensic Scientist has many areas that they could deal and work with, ranging from fingerprint analysis, blood spatter analysis, forensic odontology, evidence analysis, and crime scene technician.

There are many fields in Forensic Science. Fingerprint analysis is one of those fields.. Fingerprints are the most often found piece of evidence at a crime scene to-this-day. There are three different fingerprint patterns. There is the Loop type of fingerprint, which is the most common and are found on 60% of the people in the world. This pattern of print curves around to form a loop shape, hence the name. There also is a Whorl pattern print. This print is found on 35% of people in the world. The Whorl print can be split into four different categories; plain, which are just circles, central pocket, which is a circle with a tail at the end, double loop, which is two circles that connect to make an 'S' like pattern, and an accidental loop, which does not form anything specifically. The last type of pattern is the Arches pattern, which has a more of a wavy look. This can be split into two categories; tented, which typically rises higher, and plain tented, which is normally a lower, smoother wave. This is found on around 5% of the people in the world.

Fingerprints found at crime scenes can be put into three different categories based on what substance and or material they are marked and placed on. The first is the Patent Print. The definition of a Patent Print according to www.fingerprinting.com, is visible prints that occur when a foreign substance on the skin of a finger comes in contact with the smooth surface of another object (Types of Fingerprints 1). These are obvious to the human eye. The second type of print is the Plastic Print. This has more of a three-dimensional look. These are typically formed after a person has been in contact with a waxy substance, such as butter or soap, then touching a surface leaving a three-dimensional form print. The third type of print is the Latent Print. This type of print is the hardest print to find and is nearly impossible to see by the human eye. The print left behind is created just from the natural oils on the human skin. When looking at a scene for fingerprints, the analyst will typically use the two-step method to look for the prints. He/she will first search for Patent and Plastic Prints first because they are actually visible to the eye. The Fingerprint Analysts will use flashlights and black lights to help find any and all prints on scene. The second step is to search for the Latent Prints, the prints that are not clearly seen by the human eye. This often involves a bare physical search of the scene. The prints are most commonly found at the entryway and or exit points and on any item that appears to be tampered with or bothered. To collect Latent Prints, on either a porous or nonporous surface, there are different techniques to collect the print fully and successfully. The Powder technique is what is mainly used today. The black, dusting powder is often magnetic and is carefully brushed onto the surface and seeps into the cracks of the print, revealing a clear leftover fingerprint.

Another field in Forensic Science is the Blood Spatter field. A Blood Spatter Analysis will overlook blood stain patterns and splashes, blood drips and drops, and puddles and pools of blood. There are three types of bloodstain patterns. The first is Passive Patterns. These type of patterns happen when blood either drips or falls from the force of gravity and comes in contact with a surface. An example of this is say a gunshot wound and a person's loss of blood falling to the ground. The second type of bloodstain pattern is the Projected Bloodstain Pattern. This pattern can be put into three subcategories: low, medium, and high impact spatter. The Projected Bloodstain Pattern forms when a force or strength is put towards a person. An example of this is a person's blood spatting back after a gunshot wound onto the wall. The third type of bloodstain pattern is the Transfer/Contact Bloodstain Pattern. This pattern is pretty self explanatory. It results from an object coming in contact with any sort of blood at the scene and changing its look and or outcome from its original way. An example of this is a person with a gunshot wound stepping and slipping in a pool of blood. This Transfer/Contact Pattern can be split into two separate subcategories: wipe and swipe. The Wipe category is formed when an object just moves through a stain. The Swipe category is formed when an object leaves a stain.

Forensic Odontology is another field in the Forensic Science area. Odontologists deal with teeth and dental impressions to determine the victim and or criminal and also age and gender. The Palatal rugae, the ridges on the top of the mouth between the teeth, is a key factor in determining the gender of the victim or criminal. The size of this ranges from 25-40 mm wide. The smaller being a female and the wider being a male. Bite marks or impressions are typically found on the stomach, butt, or breasts or either the criminal or victim. It is less likely but, bite marks or impressions can also possibly be found on a piece of food around the scene. The first step to collecting these marks is to recognize if the bite it from a human or animal. If it is human, swab the mark for DNA collection, to help pinpoint the criminal or victim more accurately. For the next step, the odontologist must take multiple pictures of the bite mark because most bite marks will disappear anywhere between 5 minutes to thirty six hours after being imprinted into the skin. The odontologist will go with the body to the morgue and remove the area of skin off the victim where the bite mark is. Once this is complete, they will conserve the skin by using Formalin, a mixture of chemicals used to help maintain the skin and form a mold.

Forensic Odontology dental identification can be split into 4 different categories: Positive Dental, Probable Dental, Possible Dental. And Discarded Dental identification. The first is Positive Identification. This category deals with the teeth at the stage between antemortem, before death, by using previous dental records, and postmortem, after death. By using this identification category, the likelihood of having the exact match of someone else is 1:10,000. The second category used is the Probable Identification. This category uses more than just the teeth to identify. They use DNA and the person's bones for identification and determination. The likelihood of having an exact match of someone else in this category is 1:100. The third category is Possible Identification. This uses the obvious to try and identify. It is mainly a trial and fail technique. The Fourth and last type of identification technique is Discarded Identification. This is basically using all the leftover evidence and working with it to find another identification factor.

Forensic Pathology is another field. Pathologists deal deceased bodies to determine the time and cause of death. They determine these findings when the body is going through Rigor and Livor Mortis. Rigor Mortis is the stiffening of the muscles and tissues because of the loss of ATP, adenosine triphosphate, and occurs exactly twelve hours after death. Livor Mortis is when the blood discontinues flowing through the body, resulting in the skin turning a purplish color. This occurring between one and two hours after death. When pathologists are not out on the scene investigating, they are in the morgue performing autopsies, examination of the body during postmortem. The most common ways of dead found are death by asphyxiation, lack of oxygen, death by blunt force trauma, physical attack, death by gunshot wound, and death by stab wounds. A Pathologist will use all sorts of parts of the body to determine time and manner of death. These parts ranging from the skin, brain, hair, blood, urine, and fingernails/toenails. Autopsies can be split into three forms: Complete, Limited, and Selective. The Complete Autopsy is where a pathologist will examine every part of the whole body. A Limited Autopsy is where the majority of the body is examined, besides the head. And lastly, a Selective Autopsy is where only a certain area is analyzed. An example of this being say the brain.

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