Without evidence, the case goes cold, and in many instances they are never solved. With the use of proper evidence collection, handling and forensic science, the chances of solving a case increases dramatically. The crime scene, the evidence, the processes used, the analysis of evidence and the investigation are some of the things that make forensic science compelling. What is a crime scene? If you watch NO’S, The Closer, or ID TV, you may know that a crime scene is a location or area where a crime has been committed.
There can more than one crime scene, the primary scene is where the incident took place. There can also be secondary crime scenes in many asses, these are the areas where a weapon is found, bloody clothing has been tossed, or even where a body has been dumped, but not where the actual crime has been committed. In some cases, there can be more than one secondary scene, where as evidence has been moved to more than one place. (Plat, 2003) There are three basic crime scenes: homicide, burglary, and sexual assault.
Homicide is the killing of one person by another by shooting, strangulation or beating. When murder is the cause of death, many things must be considered. First, the body must be found if not at the rime scene, second, what was the cause of death, and third what was the time of death which can be determined by postmortem, or the examination of the corpse. Burglary is the entry to a home or building by unlawful means and removing property of the owner, but can also lead to other crimes such as vandalism, arson, sex crimes or homicide. Newton, 2008) Sexual Assault is a sexual act committed without consent of both parties by use of force. Profilers categorize rapist into four groups: power-reassurance rapists who want to live out rape fantasies. Exploitative rapists want their victim to submit to them. Anger rapists express their rape toward women with violent acts. Sadistic rapists want to hurt and dominate unwilling partners. Forensic scientists collect evidence from victims, crime scenes and suspects, including their home and workplace, to find trace evidence to connect the rapist to the victim. Newton, 2008) This is why it is very important when entering a From Crime Scene to Court Room By Summerhouses analyzed and photographed. If proper procedures are not followed, it could jeopardize or contaminate evidence that could prove or disprove a case. The response protocol is: R-respond: The first responders must secure the area and always observe and make notes about anything suspicious, to ensure proper documentation is made. E-evaluate: The first responder had to decide what type of crime has been committed and if any special units need to be called in, such as FBI or the coroner.
S-secure: Perimeters must be set around the crime scene; inner areas are for crime scene investigators and outer areas for authorized investigative personnel, making sure each person entering is logged in. P-protect: The crime scene must be protected from anything that can contaminate it, such as weather, animals or humans. It should be immediately taped off and covered if there is a chance for any disturbance to the area. O-observe: To look for or talk to any witnesses and about anything they’ve seen or heard, including fighting or gun shots.
N-notify: The first responder must call many superiors and other specialty units and give an accurate description of the situation to ensure proper authorities are present at the scene. D-document: The documentation of the observations of the crime scene must be accurate and taken at the time the observation is being made. If not done at the time, vital information can be lost or forgotten. This includes attendance log, everything that was done, seen and heard, and eyewitness statements. Dale & Becker, 2007) These are important steps to take during an investigation of a crime scene, to ensure that no evidence is lost or disturbed and to ensure the right criminal(s) will be caught. Evidence is a very important part of a crime scene; it gives investigators the needed information to catch the right criminal. As the Locator’s Exchange Principal states “that some transfer of material occurs whenever two objects make contact. ” (Newton, 2008) There are three different types of evidence, Orenstein evidence, physical evidence, and trace evidence.
Forensic evidence also known as hard evidence is what is admitted into court, this includes: testimony from a witness of the crime, direct evidence which is the observation of an eyewitness, circumstantial evidence that is information which can prove or disprove the case, and real or physical evidence that can be any object of any kind such as finger prints, weapons or blood stains, regardless of size, which can be tested and presented in court. (Campbell, 2000) Trace evidence is any evidence that is created or rendered by contact that can link persons or objects to specific locations.
These include arson, blood and bodily fluids, fibers, hair, footprints, and tire tracks to name a few. (Newton, 2008) These are all searched for at the scene of the crime and need to be processed and analyzed to solve a case. What processes are used at a crime scene? Protocol for processing a crime scene is interviews with any witnesses that may have seen or heard anything pertaining to the crime, examination of crime scene and looking for evidence, no matter how big or small it may be, and photographing he entire scene, inside and outside, before it is disturbed.
This is done to help tell the story of what happened at the scene. Sketches, which can be a solid model or a virtual model of the crime scene, gives accurate measurements and conditions of the area and processing the scene or the collecting, packing and labeling of evidence to be taken back to the crime lab. (Baldwin) When these steps are taken, it keeps the analysis. The analysis of evidence is done by forensic scientist. The collected evidence is taken to a forensics lab and processed to see if it can be used as evidence in court. Analysis takes a lot of time, contrary to what we see on TV shows.
It takes more than one forensic scientist to analyze and weeks for some evidence analysis to process. The evidence matches DNA, fingerprints, blood, bodily fluids and witness identification with the criminal to ensure the right person has been caught and to prove proof beyond a doubt. There are many different kinds of evidence used in an investigation. The typical types of evidence are blood, bullets, weapons, bodily fluids, finger prints, fibers and clothing, Just to name a few. (Plat, 2005). These types of evidence analyses use very fascinating techniques.
The typical processes that are used are fingerprint analysis, DNA analysis, and weapon and bullet analysis. Fingerprint analysis is the scanning of fingerprints into the Automated Fingerprint Identification System. It scans hundreds of prints and also cleans up smudged prints and identifies partial prints. (Frilled, 2001) Finger prints can be lifted from Just about any surface, by dusting or using iodine or a chemical mixture of dicta and fluorine to make the print glow when lit with a special light. (Plat, 2003) DNA analysis is the screening of blood, bodily fluids, hair, and nail lapping.
The DNA analysis method, multiplex polymerase chain reaction short tandem repeat – is able to show probabilities of one in a trillion or more. (Dale & Becker, 2007) Blood can be a minute drop that is tested for DNA this test is called precipitant test, it identifies if the blood belongs too human. (Plat, 2003) Weapon and bullet analysis is testing weapons such as knives, rope, or any object used to commit a murder. Matching bullets and bullet marks made from the gun, with the gun used in the crime, test firing is a must, the gun is fired into water to see if any identifying arks match to bullets used in the crime.
The gun leaves distinctive marks on the bullet from the firing pin and the ejector. These marks can only be reproduced if fired from the same gun. Every gun leaves different marks on the bullets, no two are the same. (Campbell, 2000) Stab wounds made from a sharp object or ligature marks made from any material are all important to identify in any type of crime. These leave very distinctive marks and sometimes fibers, giving investigators information to help them solve the case. (Newton, 2008) Blood stains are analyzed by their shape, size ND position.
It can also tell where the criminal stood, their height and how many times they used the weapon and which hand they used. In the crime lab, the spatter is recreated to help get a more vivid story of what happened. This recreation can be used in court to prove or disprove the defendant’s story of what happened. All evidence is then analyzed and processed, even though not all evidence is good evidence, each item has to be eliminated by analysis to ensure that nothing is lost for the investigation. These analyses are a vital part of the investigation and these steps alp prove what happened, how it happened, and who committed the crime.
Without evidence or the proper collection and handling of evidence, a criminal could go free to commit more crimes. It is extremely important for the evidence to be free of contamination. If the crime scene is contaminated, or evidence is touched or moved in any way, the evidence will be useless. Even though technology has come a long way for forensic science, there is still room for human error. The other issues intentionally fake or mishandle evidence to cover up or to wrongfully convict an innocent person.
A case against Cruz and Hernandez in 1983, a cop admitted he lied under oath; both men were exonerated in 1994 when DNA testing proved their innocents. (Ramadan, 2006) Evidence is used in court to show how the crime was committed, when the crime was committed, and who committed the crime. When evidence is not handled properly, these questions may not be answered or innocent people can be convicted of the crime they did not commit. The investigation of a crime scene begins at the crime scene and continues until the crime is tried in court.
It starts with going over the crime scene, questioning witnesses, collection and sting of the evidence, and documenting everything. After all testing and analyses are done; the information is run through several data bases, such as the AVIS or Automated Fingerprint Identification System, a database of known prints and COD’S, the Bi’s database of criminal DNA profiles. (Halloo & Welch, 2009) If there is a match or a suspect has been named, they bring them in for questioning about the crime and ask for an alibi. If the alibi checks out, they are released and further investigation is required.
Investigators often have to start back at the beginning when a suspect is cleared. In many instances, cases grow cold and many are never solved. The biggest problem that causes a case to grow cold is being unable to find physical evidence either because it was not at the scene or because it was destroyed by the offender or by law enforcement. (Fletcher, 2006) There is no statute of limitation on murder, so the evidence should be kept forever, but in many cases, detectives are pressured to get rid of things because it cost too much to store. When this happens, vital information is destroyed and the case stays cold and unsolvable.
In a few instances though, cold cases have been solved many years later through DNA testing or recollection of a witness that thought what they saw wasn’t that important and even in some cases, the offender has a change of heart and needs to confess to the crime they committed because they are ill or have had a religious experience. (Fletcher, 2006) The next time the yellow tape is there and the curiosity arises, know that a crime is being investigated. Important procedures are being used to ensure that the evidence is not disturbed for the investigators to catch the offender.