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Introduction

(Unit 1)

Forensic science is the application of science to law. Criminalistics is the application of

science to criminal and civil laws that are enforced by police agencies in a criminal justice system. In recent years these topics have become increasingly fascinating to the general population. The popularity of true crime stories has sparked a number of documentary-type television programs on both cable and network television.

History of Forensics

Sir Arthur Conan Doyle had a considerable influence on popularizing scientific crime-detection methods through his fictional character Sherlock Holmes. It was Holmes who first applied the principles of fingerprinting, firearm identification, and document examination—long before these new techniques was adopted by criminal investigators. In 1814, Mathieu Orfila published the first scientific procedures for detection of poisons and their effects on animals. It is for this text Orfila is now known as the father of forensic toxicology. Then, in 1892, Francis Galton undertook the first study of fingerprints. He focused primarily on a developing a methodology for classifying fingerprint patterns. Galton published a book entitled Finger Prints, which contained the first statistical proof supporting the uniqueness of his method of identification. His work describes the basic principles that form the present system of identification of fingerprints.

In the early twentieth-century, a technique was developed for matching a fired bullet with

a suspect gun. The determination of such information requires a comparison of the suspect bullet with one that has been test-fired from a suspect weapon. Calvin Goddard, a U.S. Army colonel, refined the techniques by utilizing the comparison microscope (two microscopes with a shared field of view).

Development of computer technology and improvement of scientific criminalistics in

recent years has significantly advanced forensic science. New techniques and technology are being developed daily to link criminals to their crimes. With the use of DNA typing, we now have the ability to identify a person from a single hair or from saliva. The ultimate goal of forensic science is to accurately and reliably link every criminal to his or her crime. Innovation in this field has vastly improved the proficiency of criminal prosecutions, punishing more criminals and exonerating the innocent.


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Basic Services Provided by Crime Laboratories

Crime labs vastly differ in size, type, specialties, and personnel management. Regardless of varying configuration, most labs can be categorized into one of the following:

Physical Science Unit The physical science unit applies principles and techniques of chemistry, physics, and geology to the identification and comparison of crime scene evidence (such as drugs, glass, paint, explosives, and soil).

Biology Unit The biology unit deals in the identification and grouping of dried bloodstains and other body fluids, comparison of hair and fiber, and the identification and comparison of botanical materials (such as wood and plants).

Firearms Unit The examination of firearms, discharged bullets, cartridge cases, shotgun shells, and ammunition of all types is conducted by the firearms unit. Garments and other objects are also examined in order to detect firearm discharge residues and to approximate the distance from a target at which a weapon was fired.

Photography Unit A complete photographic laboratory is maintained by the photography unit to examine and record physical evidence.


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The Functions of the Forensic Scientist

First and foremost, the forensic scientist is responsible for collection and analysis of physical evidence. A forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences to the study of many types of evidence that may be recovered during a crime investigation. In so doing, the scientist must also be aware of the demands and constraints that are imposed by the judicial system.

Provision of Expert Testimony

The work product of a forensic scientist may ultimately be a factor in determining a

person's guilt or innocence; he or she may be required to testify in court regarding collection methods and conclusions. It must be recognized that it is not possible for the expert to render any conclusion with absolute certainty. At best, one may only be able to offer an opinion that is based on a reasonable certainty derived from training, experience, and sound scientific procedure. Obviously, the expert is expected to defend vigorously the techniques and conclusions of the analysis, but at the same time there must be no reluctance to impartially discuss those findings that could minimize the significance of the analysis. Any attempt to do so would jeopardize the investigator’s credibility. The forensic scientist should not be an advocate of one party's cause, but only and advocate of truth.


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Standard Procedure for Approaching a Crime Scene Certainly the most important part of a crime scene is the physical evidence. Physical

evidence encompasses any and all objects that can be used to establish that a crime has been committed or can provide a link between a crime and its victim or a crime and its perpetrator. Many crimes scenes contain a large amount of possible evidence. The investigator’s challenge is to find the most applicable evidence for each particular crime scene.

It is the responsibility of the first officer arriving on the scene of a crime to take steps to

preserve and isolate the crime scene. Primarily, one should be concerned with personal safety and the well being of any victims. All efforts should be made to obtain medical assistance for individuals in need before focus shifts to perpetrator.

Next, investigators should record the crime scene. There is but a limited amount of time to examine a crime site in its unadulterated state. Although it is possible to seal off most scenes, many (like city streets or public buildings) are more difficult or impossible to secure for a significant amount of time. The opportunity to permanently record the scene in its original state must not be lost. Photography, sketches, and notes are the three methods utilized in crime scene recording.


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The most important prerequisite for photographing a crime scene is to approach it in its unaltered state. Objects must not be moved until they have been photographed from several angles, from all entryways, and close-up. The crime scene itself and its surroundings must be photographed as completely as possible. As items of physical evidence are discovered, they are photographed to show their position and location relative to the entire scene. When the size of an item is of significance, a ruler or other measuring scale may be placed in the picture with the object as a point of reference.

Once photographs are taken, the crime scene investigator will sketch the scene. Initially,

a "rough" sketch is constructed containing an accurate depiction of the dimensions of the scene, showing the location of all objects having a bearing on the case. Later, a finished sketch will be drawn by a professional draftsman. An example of a crime scene sketch appears below.

Recording observations in the form of notes must be a constant activity throughout a

crime scene’s processing. These notes must include a detailed written description of the scene with the location of items of physical evidence recovered. There should be a minimum of one note for each letter assigned on the sketch key. These notes should be descriptive, but concise. They may also include other sketches or references to pictures. Furthermore, notes should identify the time an item of physical evidence was discovered, and by whom it was discovered. The names of persons involved in packaging and labeling evidence will also appear in notes. Notes taken during the investigation may be the only source of written information about the scene, and may be used months, or perhaps years, after the scene was analyzed. The notes must be sufficiently detailed to anticipate this need.


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Collecting Evidence The following are examples of evidence which are often found and packaged, as a matter

of routine, and sent to the forensic laboratory: • Victim's clothing • Fingernail scrapings • Head and pubic hairs • Blood (for typing purposes) • Vaginal, anal, and oral swabs (in sex-related crimes) • Recovered bullets from the body and/or surrounding area • Hand swabs or washings from shooting victims (for gunshot residue analysis)

The final task at a crime scene is to collect and package the physical evidence. Physical

evidence must be handled and processed in a way that prevents any contamination between the time it is removed from the crime scene and the time it is received by the lab. In addition to foreign substances which could cause contamination, there are other problems that must be guarded against such as breakage, evaporation, accidental scratching or bending, or loss through improper or careless packaging. To protect against such contamination, each item collected must be placed in a separate container. Some pieces of evidence may require layered packaging. Packaging evidence separately and properly prevents damage, loss or degradation of samples, and prevents cross-contamination.

Whether obtained at the crime scene, from suspects, or a database, controls are one of the

most important parts of investigation. Controls are items, information, or evidence taken from a known location or individual. The examination of evidence—whether it is soil, blood, glass, hair, fiber, or others—often requires a comparison with a known standard or control. In fact, many types of evidence are useless without controls. For instance, hair found at the crime scene will be of optimum value only when compared to control hairs removed from a suspect or victim. A hair found without a control may be identified as human, but cannot be linked to the crime. Likewise, bloodstained evidence must be accompanied by whole blood controls obtained from all relevant crime scene participants, or a match cannot be made.

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An officer with the Department of Natural Resources was called to a farm where a landowner had discovered missing trees. The trees were black walnut, a valuable wood used to make expen-sive furniture. The officer found six stumps where once there were living trees. The limbs and branches were left behind. Scattered around the woods were 20 empty beer cans.

The officer examined the area and found tracks left by a truck leading across a neighbor’s field; the perpetrator of the theft had then cut through the boundary fence. By following the tracks, the officer found where the truck had slid sideways and scraped against a tree, leaving a small smear of paint. These pieces of evidence were photographed and sampled.

The landowner remembered having seen similar tire marks leading into another wooded area two miles up the road. The officer investigated these marks and found several more black walnut stumps and more empty beer cans. The officer documented numerous forms of evidence—a paint sample from the truck, tire tread impressions, and one fingerprint lifted from a beer can. The thefts stopped, and the case was considered unsolved.

Two years later, a man was caught stealing black walnut trees a couple of counties away, and his truck was impounded. The officer com-pared the original paint sample to matching paint from the truck. A receipt in the truck from a veneer mill (veneer is the thin layer of high-value wood put on the surface of low-quality woods to be used in furniture) suggested that the man had been selling logs for some time.

The paint on his truck was consistent with paint found at the crime scene, and his fingerprints matched the fingerprint found on the beer can at the scene. Based on the evidence, he was convicted, fined, and sent to prison for six years. An observant investigator was able to collect sufficient evidence for a jury to find the man guilty of stealing the trees.

Was Someone Stealing the Trees?

Observation Skills

CHAPTER

An investigator examines paint evidence.

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Copyright 2016 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. WCN 02-200-203

MATHEMAMATHEMAMA TICSTHEMATICSTHEMALITERACY

PHYSICSEARTH SCIENCES

CHEMISTRYBIOLOGY

TOPICAL SCIENCES KEY

VOCABULARY

By the end of this chapter, you will be able to:

1.1 Define observation, and describe what changes occur in the brain while observing.

1.2 Describe examples of factors influencing eyewitness accounts of events.

1.3 Compare the reliability of eyewitness testimony to what actu-ally happened.

1.4 Relate observation skills to their use in forensic science.

1.5 Define forensic science.

1.6 Practice and improve your own observation skills.

OBJECTIVESOBJECTIVES

3O B S E R V A T IO B S E R V A T IO B S E R V A T I OOO N N N SSS K I L L SK I L L SK I L L S

◾ analytical skills the ability to identify a con-cept or problem, to isolate its component parts, to organize information for decision making, to establish criteria for evaluation, and to draw appropriate conclusions

◾ deductive reasoning deriving a conclusion from the facts using a series of logical steps

◾ eyewitness a person who has seen someone or something related to a crime and can com-municate his or her observations

◾ fact a statement or information that can be verified

◾ forensic relating to the application of scien-tific knowledge to legal questions

◾ logical reasoned from facts

◾ observations what a person perceives using his or her senses

◾ opinion personal belief founded on judgment rather than on direct experience or knowledge

◾ perception information received from the senses


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INTRODUCTION

One of the most important tools of the forensic investigator is the abilforensic investigator is the abilforensic -ity to observe, interpret, and report observations clearly. Whether observing at a crime scene or examining collected evidence in the laboratory, the forensic exam-iner must be able to identify the evidence, record it, and determine its significance. The trained inves-tigator collects all available evi-dence, without making judgments about its potential importance. That comes later. Knowing which evidence is significant requires the ability to re-create the series of events preceding the crime. The first step is careful and accurate observation (Figure 1-1).

WHAT IS OBSERVATION? Obj. 1.1, 1.4

Every single moment, we are gathering information about what is around us, through our senses—sight, taste, hearing, smell, and touch. We do this largely without thinking, and it is very important to our survival. Why are we not aware of all the information our senses are gathering at any time? The simple answer is that we cannot pay attention to everything at once. Instead of a con-stant flow of data cluttering up our thoughts, our brains select what informa-tion they take in; we unconsciously apply a filter (Figure 1-2). We simply pay attention to things that are more likely to be important. What is important is decided by various factors, including whether the environment changes. For example, if you are sitting in a room and everything is still, you are unlikely to be filled with thoughts about the color of the sofa, the shade of the light, or the size and shape of the walls. But if a cat walks in, or you hear a loud bang, you will perceive these changes in your environment. Paying attention to the details of your surroundings requires a conscious effort.

Figure 1-2 How information is processed in the brain.

Informationfrom oursenses

What we payattention to

PerceptionShort-termmemory

Long-termmemory

Figure 1-1 A crime scene is often laid out in a grid to ensure that all evidence is found.

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O B S E R V A T I O N S K I L L S 5

It is difficult to believe, but our brains definitely play tricks on us. Our perception is limited, and the way we view our surroundings may not accurately reflect what is really there. Perception is faulty; it is not always accurate, and it does not always reflect reality. For example, our brains will fill in information that is not really there. If we are reading a sentence and a word is missing, we will often not notice the omission but instead predict the word that we think should be there and read the sentence as though it is complete.

Our brains will also apply knowledge we already have about our sur-roundings to new situations. In experiments with food coloring, a creamy pink dessert is perceived to be strawberry flavored even though it is vanilla flavored. Our minds have learned to associate pink with strawberries and apply that knowledge to new situations—even when it is wrong. An interest-apply that knowledge to new situations—even when it is wrong. An interest-apply that knowledge to new situations—even when it is wrong. An interesting aspect of our perception is that we believe what we see and hear, even though our ability to be accurate is flawed. People will stick to what they think they saw, even after they have been shown that it is impossible.

If you are feeling like your brain is defective, do not worry: the brain, while faulty, is still good at providing us with the information we need to survive. Filtering information, filling in gaps, and applying previous knowl-edge to new situations are all useful traits, even if they do interfere some-times. Understanding our limitations helps us improve our observation skills, which is extremely important in forensic science. Criminal investiga-tions depend on the observation skills of all parties involved—the police investigators, the forensic scientists, and the witnesses.

OBSERVATIONS BY WITNESSES

Obj. 1.2, 1.3, 1.4, 1.6

One key component of any crime investigation is the observations made by wit-One key component of any crime investigation is the observations made by wit-One key component of any crime investigation is the observations made by witnesses. Not surprisingly, the perceptions of witnesses can be faulty, even though a witness may be utterly convinced of what he or she saw. Have you ever noticed that you can walk along the street or ride in a car and be totally unaware of your surroundings? You may be deeply involved in a serious conversation on your cell phone and lose track of events happening around you. Your focus and concentration may make an accurate accounting of events difficult.

Our emotional state influences our ability to see and hear what is happen-ing around us. If people are very upset, happy, or depressed, they are more likely not to notice their surroundings. Anxiety also plays a big part in what we see and what we can remember. Our fear at a stressful time may interfere with an accurate memory. Victims of bank robberies often relate conflicting descriptions of the circumstances surrounding the robbery. Their descrip-tions of the criminals committing the robbery often do not match.

It is difficult to believe, but our brains definitely play tricks on us. Our

is limited, and the way we view our surroundings may not accurately reflect what is really there. Perception is faulty; it is not always accurate, and it does not always reflect reality. For example, our brains will fill in information that is

Can a beer can in the woods lead to a conviction? A smashed dial on a safe betray the suspect? They have, and now it’s your turn. Search the Gale Forensic Science eCollection on ngl.cengage.com/forensicscience2eto find a case study and demonstrate in writing how good observation skills led to the solution of a crime.

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Nevertheless, eyewitness accounts of crimes can be valuable evidence (Figure 1-3). Bystanders who are unaware that they are watching a crime unfold are not subject to the anxiety victims are, and may provide valuable evidence. And some victims are less subject to the disruptive effects of anxiety on memory.

Other factors affecting our observational skills include:

• Whether you are alone or with a group of people• The number of people and/or animals in the area• What type of activity is going on around you• How much activity is occurring around you

All of these factors influence the accuracy of a witness’s observations.

Eyewitness AccountsWhat we perceive about a person depends, in part, on his or her man-nerisms and gestures. How a person looks, walks, stands, and uses hand gestures all contribute to our image of his or her appearance. Think about your family members. How would you describe them? What makes them unique? We also form images of familiar places. Our homes, school, and

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Figure 1-3 This eyewitness is searching a mug book for previous offenders who might have committed the crime she witnessed.



other places we often visit (e.g., a favorite store or restaurant) are burned into our memories and easy to recognize and remember.

Eyewitness accounts of crime-scene events vary considerably from one per- accounts of crime-scene events vary considerably from one per- accounts of crime-scene events vary considerably from one person to another. What you observe depends on your level of interest, stress, con-centration, and the amount and kind of distraction present. Our prejudices, personal beliefs, and motives also affect what we see. Memory fades with time, and our brains tend to fill in details that we feel are appropriate but may not be accurate. These factors can decrease an eyewitness’s accuracy in recalling a crime. The testimony of an eyewitness can be very powerful in persuading the jury one way or another; knowing the shortcomings of eyewitness testimony is necessary to ensure that justice is carried out appropriately.

The Innocence ProjectThe Innocence Project at the Benjamin N. Cardozo School of Law at Yeshiva University in New York was created by Barry C. Scheck and Peter J. Neufeld in 1992. Its purpose is to reexamine post-conviction cases (individuals convicted and in prison) using DNA evidence to provide conclusive proof of guilt or innocence (Figure 1-4). After evaluating hundreds of wrongful convictions in the United States, the Innocence Project found that faulty eye-witness identification contributed up to 87 percent of those wrongful convictions. Eyewitness errors included mistakes in describing the age and facial distinctiveness of the sus-pect. These mistakes resulted from disguised appearances, too-brief sightings of the perpetrator, cross-gender and cross-racial bias, and changes in the viewing environment (from crime scene to police lineup).

When evaluating eyewitness testimony, the investigator must discriminate between fact and fact and fact opinion. What did the witness actually see? Often what we think we saw and what really happened differ. Someone fleeing the site of a shooting might look like a suspect but could merely be an innocent bystander running away in fear of being shot. Witnesses have to be carefully examined to ensure that they describe what they saw (eyewitness evidence), not what they thought happened (opinion).

After witness examination, the examiner tries to piece together the events (facts) of the crime into a logical pattern. logical pattern. logicalThe next step is to determine if this pattern of events is veri-fied by the evidence and reinforced by the witness testimony.

How to Be a Good ObserverWe can apply what we know about how the brain processes information to improve our observation skills. Here are some basic tips:

1. We know that we are not naturally inclined to pay attention to all of the details of our surroundings. To be a good observer, we must make a conscious effort to examine our environment systematically. For example, if you are at a crime scene, you could start at one corner of the room and run your eyes slowly over every space, looking at everything you see. Likewise, when examining a piece of evidence on a microscope slide, look systematically at every part of the evidence.

BIOLOGY

Figure 1-4 Gary Dotson was the first individual shown to be innocent by the Innocence Project.

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2. We know that we are naturally inclined to filter out information we assume is unimportant. However, at a crime scene, we do not know what may turn out to be important. In this situation, we need to consciously observe everything, no matter how small or how familiar, no matter what our emotions or previous experiences. So we train ourselves to turn off our filters, and instead act more like data-gathering robots.

3. We know that we are naturally inclined to interpret what we see, to look for patterns, and make connections. To some degree, this inclination can lead to us jump-ing to conclusions. While observing, we need to be careful that we concen-trate first and foremost on gathering all of the available information and leaving the interpretation until we have as much information as possible. The more information we have, the better our interpretations will be.

4. We know that our memories are faulty. While observing, it is important to write down and photograph as much information as possible (Figure 1-5). This will become very important later when we, or our investigating team members, are using our observations to try to piece together a crime. Documentation also is important when acting as an expert witness. A judge will only accept hair evidence that has been documented in writing and with photographs taken at the crime scene. The verbal testimony of a forensic scientist alone may not be entered into evidence without the proper documentation.

Figure 1-5 Documentation is an essential part of observation.

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Observation is as much about finding evidence as it is about spot-ting patterns of criminal behavior. We know that, on average, most thieves who come in through a window will leave by a door. Search the Gale Forensic Science eCollection on ngl.cengage.com/forensicscience2e for articles on patterns of criminal behavior. Discuss with the class how a knowledge of criminal behavioral pat-terns can help to solve crimes.

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FORENSIC SCIENCE Obj. 1.5

Forensic science the word conjures up images of Forensic science the word conjures up images of Forensic science CSI: Miami, lab coats, and dimly lit laboratories. “Forensic” derives from the Latin word forensis, which means “of the forum.” The ancient Roman forum was an open area where scholars would gather to debate issues.

But forensics today is science. The debating comes later, in the court-But forensics today is science. The debating comes later, in the court-But forensics today is science. The debating comes later, in the courtroom, after the scientific analysis of the evidence. Science is formally defined as the use of evidence to construct testable explanations and pre-dictions of phenomena and the knowledge generated through this process. Note that science is a process. Observations lead to a testable hypothesis, a tentative explanation of observations that may or may not be supported by testing. Through repeated testing and revising of hypotheses, diseases can be cured and serial killers can be caught.

Note that a hypothesis is not a theory; neither in the sense of “I have a theory as to where Amelia’s lost cat is,” nor in the sense of a scientific theory. Like a hypothesis, a scientific theory is based on natural and physical phe-nomena and must be capable of being tested by independent researchers and subject to alteration as developing science and technology yield new data. But unlike a hypothesis, a theory has been well-established and supported by test-unlike a hypothesis, a theory has been well-established and supported by test-unlike a hypothesis, a theory has been well-established and supported by testing and is highly reliable. Newton’s physical theory of gravity, and the theories of evolution and general relativity have been supported by more than a century of data from diverse scientific disciplines.

What Forensic Scientists DoSo—what do forensic scientists do? Their task is to find, examine, and evalu-ate evidence from a crime scene. A good forensic scientist is skilled at making observations and applying scientific knowledge to analyze the crime scene. Forensic scientists are bound by ethics to find as much evidence as possible and to fully analyze and interpret it, with all the accuracy and skill of which they are capable, without personal bias. A forensic scientist must also be a good com-municator who is able to convince a jury that his/her analysis is both reliable and accurate (Figure 1-6). Often specialists deal only with certain types of evidence. Ballistics experts work with bullets and firearms; pathologists work with bodies to determine the cause of death through the examination of injuries. Textile experts, blood-spatter experts, and vehicle experts all rely on observation skills to do their jobs.

Police officers must also be trained to have good observation skills. Part of their training is learning to take in the entire scene before making an assessment based on their observations. The ability to solve a crime depends on observing all of the evi-dence left at a crime scene. Analytical skillsof this type require patience and practice.

Figure 1-6 A forensic scientist acting as an expert witness in court.

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High-ranking police officers in New York City are trained in observation skills at a local museum, the Frick Collection. The police learn to identify details in the paintings and draw conclusions about the paintings’ subjects. They apply their new skills at crime scenes.


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The character Sherlock Holmes had excellent observation skills that made him an extraordinary detective. He could find clues in ordinary details others missed. Then, he worked backward from the evidence to piece together the crime. This process is deductive reasoning. These abili-ties to observe a situation, organize it into its component parts, evaluate it, and draw appropriate conclusions are all valuable analytical skills used by today’s police detectives.

NONFICTIONREADINGS

Ekman, Paul, Emotions Revealed

LITERACY

In 1831, three men aged 33, 30, and 26 were tried in a court in London, England, for the murder of a 15-year-old Italian immigrant, Carlo Ferrier. John Bishop, James May, and Thomas Williams brought the body in a sack to a local university, King’s College, seeking money in exchange for the corpse. It was common prac-tice at the time for universities and hospitals to buy bodies of people who had died from natural causes to use for anatomy lessons and research. However, the university staff member noticed that this body looked particularly fresh, and he turned the three men over to the police because of his suspicion. The conviction of the suspects rested on a variety of evidence that was collected because of excellent observation skills. A surgeon

CASE STUDIESCarlo Ferrier ( 1831 )

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SUMMARY

• Our ability to observe is affected by our environment and the natural filters of sensory information in our brains.

• The observations of witnesses to crimes can be faulty, but in some cases can be precise.

• The Innocence Project has found that up to 87 percent of their wrongful conviction cases resulted from flawed eyewitness testimony.

• Police officers and crime-scene investigators are trained in good obser-vation practices.

• Forensic scientists find, examine, photograph, document, and evaluate evidence from a crime scene and provide expert testimony to courts.



Three Wrongful Convictions

In August 2003, charges were dropped against two men who were wrongly identified and imprisoned for 27 years based on a faulty eyewitness account. In 1976, Michael Evans and Paul Terry were tried and sent to prison for the rape and murder of nine-year-old Lisa Cabassa. They were convicted on the testimony of one purported witness. DNA tests proved that the men were not guilty of the charges.

In a Florida case, death row inmate Frank Lee Smith died of cancer in January 2000 while in prison. He was convicted in 1986 of the rape and murder of an eight-year-old child, even though no physical evidence was found. He was found guilty largely on the word of an eyewitness. Four years after the crime, the eyewitness recanted her testimony, saying she had been pressured by police to testify against Smith. Despite this information, prosecutors vigorously defended the conviction and refused to allow Smith a postconviction DNA test he requested. After his death, the DNA test exon-erated him.

Think Critically

Review the Case Studies and the information on observation in the chapter. Then state in your own words how eyewitness evidence impacts a case.

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carefully examined the body and noticed that all of the organs were healthy; the cause of death did not appear natural. Blood pooled around the spinal cord at the back of the neck was the only sign of violence, and was in keeping with what would be expected from a blow to the back of the neck. Other evidence included bloodstained clothes belonging to the dead boy, which were found buried in the back garden of the accused. These articles were recovered when a policeman inspecting the residence noticed a patch of soft earth in the garden. Bishop, May, and Williams were sentenced to death.


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C H A P T E R 1

▸ Lie Detector▸ FaceORama▸ SoER Free

Learn More About It▸ To learn more about Paul Ekman and the work of

forensic psychologists, go to ngl.cengage.com/forensicscience2e.

Careers in Forensics

Very few people can lie to Paul Ekman and get away with it. He can read faces like an open book, spotting the most subtle changes in expression that reveal if a person is lying. A psychologist who has spent the last 50 years studying faces, Ekman is a leading expert on facial analysis and deception. This skill puts him in high demand by law-enforcement groups around the world, such as the Federal Bureau of Investigation (FBI), Central Intelligence Agency (CIA), Scotland Yard, and Israeli Intelligence.

When looking for deception, Ekman watches for inconsistencies, such as facial expressions that do not match what is being said. He can also detect what are called microexpres-sions—rapid changes in expression that last only a fraction of a second but reveal a person’s true feelings. It is a rare talent to be able to spot these microexpressions. Only 1 percent of people are able to do so without training.

Ekman was the first to determine that a human face has 10,000 possible configurations and which muscles are used in each. He then created the Facial Action Coding System. This atlas of the human face is used by a variety of people looking to decode human expression, including investigators, psychol-ogists, and even cartoon animators.

Ekman has turned his expert gaze onto many famous faces. He thinks the mysterious Mona Lisa is flirting, and he can identify the exact facial mus-cles a witness uses when he lies in court. He has

studied tapes of Osama bin Laden to see how his emo-tions changed leading up to the 9/11 terrorist attacks.

Ekman first became inter-Ekman first became inter-Ekman first became interested in facial expressions at the age of 14, after his mentally ill mother com-mitted suicide. He hoped to help others like her by understanding emotional disorders. From his expe-rience as a photogra-pher, he realized that facial expressions would serve as a perfect tool for reading a person’s emotions.

Ekman’s early research led to a major

discovery that changed how scientists view human expression. Experts used to believe that facial expressions were learned, but Ekman thought otherwise. He traveled around the world and found that facial expressions were universally understood, even in remote jungles where natives had never before seen a Westerner. It could mean only one thing: our expressions are biologically programmed. This opened the door for Ekman to study human expression in a completely new way.

Fifty years of groundbreaking research fol-lowed Ekman’s discovery. He served first as Chief Psychologist for the U.S. Army, and then as a pro-fessor at the University of California. Now in his eighties, Ekman continues to train others to detect deception and improve safety and security. His work was the basis for the TV series Lie To Me.

Paul Ekman

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A psychologist who has spent the last 50 years studying faces, Ekman is a leading expert on facial analysis and deception. This skill puts him in high demand by law-enforcement groups around the world, such as the Federal Bureau of Investigation (FBI), Central Intelligence Agency (CIA), Scotland

When looking for deception, Ekman watches for inconsistencies, such as facial expressions that do not match what is being said. He can

studied tapes of Osama bin Laden to see how his emotions changed leading up to the 9/11 terrorist attacks.

ested in facial expressions at the age of 14, after his mentally ill mother committed suicide. He hoped to help others like her by understanding emotional disorders. From his expe

Cou

rtes

y, D

r. P

aul

Ekm

an

Paul EkmanPaul Ekman


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