The importance of forensic science in criminal investigations

Publicado en Criminalística

The importance of forensic science in criminal investigations

Imagine a world where criminals run freely.  Detectives and police officers collect evidence much the same way as they do today, but there is one main difference.  Science is not used.  Due to the lack of scientific analysis, there would not be a lot of useful evidence.  Without the use of science, criminals could not be convicted of their crimes, ranging from common theft to a homicidal rampage, unless there was an eyewitness present at the crime scene when the crime occurred.  Murderers would continue killing, thieves would continue stealing, and drug traffickers would continue dealing.  Fortunately, in today's world, science is used in solving crimes.  Clues a criminal leaves behind can be traced to themselves through scientific evidence.  This field of science dealing with criminal investigation is known as forensic science, which roughly means the application of science to law (Microsoft 200).  Forensic science can be used to determine many things from the evidence when it is collected properly without any contamination.  The people that need to learn the methods of collecting the evidence for forensic science analysis are those from law enforcement agencies that come into contact with the crime scenes frequently.
Unfortunately, nine times out of ten, this person is an officer from a police department, which is lacking in evidence collection training.  In other words, scientific concepts and principles are used to convict criminals of their crimes.  Due to the great importance of forensic science in the conviction of criminals, the basic ideas and concepts need to be taught to officers of local police departments so that evidence can be collected without contamination in order to keep criminals, such as the Manson “family” and O. J. Simpson, from continuing to commit crimes that linger on forever in the minds of the victim’s families and the nation's psyche.  The evidence collected in the Manson murders known as the "Tate" murders and that from the O. J. Simpson case was in many ways done improperly.  The improper collection and the use of various unsterilized items contaminated the evidence,  making it worthless to the two individual cases.  Police departments need to know how to handle evidence to make sure these mistakes do not happen again.

Throughout history, evidence has been used to convict criminals of the crimes that they have committed.  Today’s society has improved upon the methods of the past to bring about more precise and accurate techniques.  These techniques are more commonly known as the field of forensic science.  Richard Saferstein writes a more specific definition than what was previously given in his book Criminalistics:  An Introduction to Forensic Science, which says that forensic science is the “application of science to those criminal and civil laws that are enforced by the police agencies in a criminal justice system (Saferstein 1).”  The origin of this type of science cannot be accurately pinpointed.  According to H. J. Walls' article “Whither Forensic Science?” it started as a hobby of a few scientists who liked to become mixed up in the proceedings of the police and “enjoyed the kind of problems this association brought them (Walls 32).”  We do not know how forensic science originated and came together or how it came to be connected to the police investigations and court rulings.  According to Cowan in his article “Decision Theory in Law, Science, and Technology”

“The aim of science, traditionally put, is to search out the ways in which truth may become known.  Law aims at the just resolution of human conflict.  Truth and justice, we might venture to say, having different aims, use different methods to achieve them.  Unfortunately, this convenient account of law and science is itself neither true nor just.  For law must know what the truth is within the context of the legal situation:  and science finds itself ever engaged in resolving the conflicting claims of theorists putting forward their own competing brands of truth (Cowan 5).”

This quote roughly means that the law needs to find the truth to resolve “human conflict” and one method of doing so is to use the field of science.  The only problem with this method is that science is struggling to find the correct truth.  Different scientists supply various ways of what is known as the truth, but sometimes these truths differ.  An example of the differing opinions is shown in what scientists believe caused the extinction of the dinosaurs.  Several scientists believe in the asteroid impact theory, in which giant asteroid fell to the earth.  This caused a cloud of dust to erupt into the earth’s atmosphere, blocking all sunlight.  Those that did not die in the initial impact died of starvation.  Other beliefs include a massive plague that infected all of the dinosaurs and severe global warming due to the gases from the volcanoes (ETE Team 2001).  The three beliefs given about the dinosaurs are just examples of the differing opinions among scientists.

An excellent example of the need for the proper collection of evidence for forensic science analysis in criminal investigations would be the Manson “family” "Tate" murders of the late 1960s.  These crimes took place near the city of Los Angelos in California.  Two people, Abigail Folger and Voytek Frykowski, were found lying on the rear grounds of the Tate property in the grass.  Folger had been stabbed a total of twenty-eight times and Frykowski was shot twice, stabbed fifty-one times, and brutally hit over the head thirteen times.  Steven Parent was also found on the outside premises of the estate.  He was shot four times and stabbed once while in his car.  The other two victims of the “Tate” murders, Sharon Tate Polanski and Jay Sebring, were found in the inner part of the house tied together by a single rope surrounding both their necks that was knotted to a ceiling rafter.  Neither of these two unfortunate people died from the hanging.  Polanski, who was at the time eight months pregnant, took sixteen stab wounds to both her back and her chest.  Sebring, stabbed seven times and shot once, died from exsanguinations, which means bleeding to death.  The Los Angeles police department, LAPD, worked on this set of murders (Bugliosi 1974).  The department did not have sufficient training to collect the evidence found at the crime scenes.  Due to this fact many mistakes were made.

The first mistake, made by the LAPD officers, occurred shortly after arrival at the Tate residence.  The officers, in an attempt to cover the bodies of the dead, put blue sheets found in a linen closet over the bodies (Bugliosi 1974).  This was not wise because small fibers from the sheets covered the victim’s bodies, and these fibers mixed in with the other fibers that were already on the bodies.  These could have easily been from the garments that the murderer or murderers had worn.  They could have been observed through a microscope for the diameter, length, surface texture, and many other characteristics (Turner 1949).  These results would then be compared to the known fibers that have been entered into a database for easy reference.  After the fibers already on the body had been contaminated by the sheet fibers, they were deemed practically useless.

The other mistake that was made with these blue sheets involved the amount of time that they were on the bodies.  A week after the LAPD arrived, the blue sheet that was on the body of Abigail Folger was still there (Bugliosi 1974).  The sheets were not a well thought out plan, but leaving the bodies out in the open for that amount of time was far worse.  The bodies needed to be taken to a medical examiner immediately to have an autopsy completed to determine how long the individual had been dead and the cause of death (Larson 1999).

Fingerprints can be the key evidence to any investigation; however, in the Manson investigation they were a key problem.  An LAPD officer took notice of a spot of blood on the button that opened the gate to the Tate estate while escorting a possible suspect up to the mansion.  According to Vincent Bugliosi, in his book Helter Skelter, he reported that the officer "who was charged with securing and protecting the scene until investigating officers arrived, now pressed the button himself, successfully opening the gate but also creating a superimposure that obliterated any print that may have been there. (p 14)”  Basically, what this means is that the officer saw the blood on the button and then either did not have enough common sense not to push the button or simply did not care whether he damaged a crucial piece of evidence.  Another piece of evidence, the gun used in the crimes, was reported to have more fingerprints that belonged to officers than the fingerprints of the perpetrators.
About two weeks after the murders at the Tate property were reported, a boy found the weapon and brought it to the attention of the authorities.  E. Sanders in his book The Family commented, “The boy was careful not to touch the revolver to protect fingerprints.  The police smudged it up and filed it away, the chambers of the weapon containing seven spent shells and two live bullets. (p 355)”  Apparently the young boy was more careful with the evidence than the slightly trained police officers.
Perhaps he should have been the one collecting the evidence and not the professionals.  Due to the mishandling of the gun the fingerprints that were on it could not be identified.  Fortunately, a fingerprint for the front door of the house and another that was lifted from Polanski’s bedroom matched two of the suspects (Bardsley 2001).  Using fingerprints to identify people has been in practice since around 1860.  A very basic definition of a fingerprint is that it is a print of the design of the “friction skin ridges” on the “palm side” of a finger.  There are three main patterns, or ridge characteristics, that can be used to identify each person:  arches (5% of all fingertips), loops (60%), and whorls (35%) (Inbau 25).  The placement of each of these qualities is different from person to person, no two are alike. -Manson Gun (Bardsley 2001)