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Forensic Science

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Forensic Science

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    1. Forensic Science

    5. A forensic scientist studies and analyzes physical evidence used in criminal court cases.

    7. Forensic Scientists can specialize in a variety of different areas:

    8. The Expert Witness is bound by ethics to report the truth, regardless of the outcome to his client. They are called on by lawyers to report, in a fashion that the jury can understand, the specifics of the case. Professional integrity, above all else, is critical to an expert witness. The Expert Witness is bound by ethics to report the truth, regardless of the outcome to his client. They are called on by lawyers to report, in a fashion that the jury can understand, the specifics of the case. Professional integrity, above all else, is critical to an expert witness.

    9. What personal attributes are desirable in a good forensic scientist?

    17. Forensic Pathologist Forensic pathologists are medical doctors, physicians, with a specialization in forensic pathology. They perform autopsies in an effort to establish the cause of death. The forensic pathologist's general focus in on soft tissue (including organs and body fluid analyses). The forensic pathologist, in addition to natural disease processes, is also involved with injuries and unnatural illnesses and deaths. If a person dies soon after an injury a forensic pathologist may be called upon to determine whether the death was or was not related to the injury. The forensic pathologist be able to recognize all types of injuries, their causes and effects. Typically, the forensic pathologist is given the responsibility of investigating suspicious or unexplained deaths and to establish the cause and manner of death in such cases.Forensic pathologists are medical doctors, physicians, with a specialization in forensic pathology. They perform autopsies in an effort to establish the cause of death. The forensic pathologist's general focus in on soft tissue (including organs and body fluid analyses). The forensic pathologist, in addition to natural disease processes, is also involved with injuries and unnatural illnesses and deaths. If a person dies soon after an injury a forensic pathologist may be called upon to determine whether the death was or was not related to the injury. The forensic pathologist be able to recognize all types of injuries, their causes and effects. Typically, the forensic pathologist is given the responsibility of investigating suspicious or unexplained deaths and to establish the cause and manner of death in such cases.

    18. Forensic Psychologist A forensic psychologist assists in court. They can play a number of key roles in a criminal investigation. Immediately following a crime a forensic psychologist may be asked to act as a criminal profiler. Criminal profiling involves using his/her understanding of human behavior, motivation, and pathology so that he/she can create a psychological profile of the offender. In the court system, forensic psychologists are frequently used for both criminal and civil cases. In the criminal area, the forensic psychologist is often asked to assess competency. Forensic psychologists may also be asked to make an evaluation regarding the defendant's mental state at the time of the offense. The entire "not guilty by reason of insanity" defense relies on the psychological evaluation of a defendant's inability to form criminal intent. Most Forensic Psychologists work either in a correctional institution (i.e., prison, jail, or juvenile hall) or in a psychiatric hospital. In this environment, one of their most essential roles is to provide a range of therapies in order to control the mental disorder that has led to the offenders criminal acts. Certain disorders (i.e., obsessions, schizophrenia, bipolar depression, addictions) that can be correlated to criminal behavior can often be treated satisfactorily, others (i.e., antisocial behavior disorder) are far less successfully controlled. Before, and after, treatment the forensic psychologist may perform diagnosis and psychometric testing (the evaluation of behavior/personality via tests/surveys) in order to evaluate the clients risk of violence and/or recidivism (the likeliness that the criminal will recommit the crime). These evaluations are very important to future parole and competency hearings.A forensic psychologist assists in court. They can play a number of key roles in a criminal investigation. Immediately following a crime a forensic psychologist may be asked to act as a criminal profiler. Criminal profiling involves using his/her understanding of human behavior, motivation, and pathology so that he/she can create a psychological profile of the offender. In the court system, forensic psychologists are frequently used for both criminal and civil cases. In the criminal area, the forensic psychologist is often asked to assess competency. Forensic psychologists may also be asked to make an evaluation regarding the defendant's mental state at the time of the offense. The entire "not guilty by reason of insanity" defense relies on the psychological evaluation of a defendant's inability to form criminal intent. Most Forensic Psychologists work either in a correctional institution (i.e., prison, jail, or juvenile hall) or in a psychiatric hospital. In this environment, one of their most essential roles is to provide a range of therapies in order to control the mental disorder that has led to the offenders criminal acts. Certain disorders (i.e., obsessions, schizophrenia, bipolar depression, addictions) that can be correlated to criminal behavior can often be treated satisfactorily, others (i.e., antisocial behavior disorder) are far less successfully controlled. Before, and after, treatment the forensic psychologist may perform diagnosis and psychometric testing (the evaluation of behavior/personality via tests/surveys) in order to evaluate the clients risk of violence and/or recidivism (the likeliness that the criminal will recommit the crime). These evaluations are very important to future parole and competency hearings.

    19. Forensic Anthropologist The forensic anthropologist's general focus in on bones. Forensic anthropologists are experienced osteologists (bone specialists). When the only remains of a body are bony remains, a forensic anthropologist will be called in to help with the identification. Forensic anthropologists usually hold a doctorate degree (Ph.D.); but many have a Master's degree (MA) in anthropology. Forensic anthropologists with advanced (graduate) degrees usually (but not always) work in an academic setting--at a college or university. This employment setting involves teaching courses, conducting research, and providing service--such as forensic consultation services. Other employment settings for forensic anthropologists can include work in laboratories (FBI, state bureaus of investigation, or private firms), or medical examiner/coroner facilities nationwide and worldwide. The forensic anthropologist's general focus in on bones. Forensic anthropologists are experienced osteologists (bone specialists). When the only remains of a body are bony remains, a forensic anthropologist will be called in to help with the identification. Forensic anthropologists usually hold a doctorate degree (Ph.D.); but many have a Master's degree (MA) in anthropology. Forensic anthropologists with advanced (graduate) degrees usually (but not always) work in an academic setting--at a college or university. This employment setting involves teaching courses, conducting research, and providing service--such as forensic consultation services. Other employment settings for forensic anthropologists can include work in laboratories (FBI, state bureaus of investigation, or private firms), or medical examiner/coroner facilities nationwide and worldwide.

    20. Criminalist Criminalists examine and identify physical evidence to reconstruct a crime scene. Physical evidence can be a weapon, a piece of clothing, a bloodstain, drugs, or even a vapor in the air. Criminalists use physical evidence to provide a connection between the suspect and the victim. Such connections are acquired by the transfer of hair or clothing fibers from a suspect to the victim. Other connecting links are fingerprints, bullets, or shoe impressions. Physical evidence is collected from a crime scene that includes the victim's body and the surrounding area of the crime. Criminalists examine and identify physical evidence to reconstruct a crime scene. Physical evidence can be a weapon, a piece of clothing, a bloodstain, drugs, or even a vapor in the air. Criminalists use physical evidence to provide a connection between the suspect and the victim. Such connections are acquired by the transfer of hair or clothing fibers from a suspect to the victim. Other connecting links are fingerprints, bullets, or shoe impressions. Physical evidence is collected from a crime scene that includes the victim's body and the surrounding area of the crime.

    21. Forensic Entomologist The time of death can usually be determined using insect evidence gathered from and around a corpse. Forensic entomologists are also requested to examine the fragmented remains of insects that have impacted and lodged on the front fascia, windshield, and radiator of automobiles. Analysis of such remains can yield evidence to the probable path of an automobile through particular areas when pinpointing the location and areas of travel are of unique importance. The time of death can usually be determined using insect evidence gathered from and around a corpse. Forensic entomologists are also requested to examine the fragmented remains of insects that have impacted and lodged on the front fascia, windshield, and radiator of automobiles. Analysis of such remains can yield evidence to the probable path of an automobile through particular areas when pinpointing the location and areas of travel are of unique importance.

    22. Forensic Engineer The forensic engineer offers engineering investigation services directed toward insurance adjusters, attorneys, and manufacturers. Examples of their work might include: Stairway trip and fall. Person lost balance due to irregularity of stairs and sustained injuries. Stairs were improperly constructed. Wall collapse Six foot high concrete block wall fell on workman causing amputation and other injuries. Modeling of accident showed who was responsible. Pavement failure. Automobile hit large pothole in a city street causing severe damage to occupant. Showed how hole might have been obscurred by water. Electric shock. Person fell into ditch caused by erosion at which time contact was made with a hot guy wire causing amputation of a portion of arm. Computer aided modeling was necessary. To show sequence of events. Scaffolding failure. Scaffold improperly erected failed, injuring workman. Off-road vehicle accident. Occupant of vehicle being used improperly suffered fatal injuries. Topography of site showed how accident happened. Auto accident. Poor road design was contributing factor causing accident. Computer modeling was used to show friction factors. Failure Analysis/Hazard Analysis of Consumer Products Workplace Accident InvestigationThe forensic engineer offers engineering investigation services directed toward insurance adjusters, attorneys, and manufacturers. Examples of their work might include: Stairway trip and fall. Person lost balance due to irregularity of stairs and sustained injuries. Stairs were improperly constructed. Wall collapse Six foot high concrete block wall fell on workman causing amputation and other injuries. Modeling of accident showed who was responsible. Pavement failure. Automobile hit large pothole in a city street causing severe damage to occupant. Showed how hole might have been obscurred by water. Electric shock. Person fell into ditch caused by erosion at which time contact was made with a hot guy wire causing amputation of a portion of arm. Computer aided modeling was necessary. To show sequence of events. Scaffolding failure. Scaffold improperly erected failed, injuring workman. Off-road vehicle accident. Occupant of vehicle being used improperly suffered fatal injuries. Topography of site showed how accident happened. Auto accident. Poor road design was contributing factor causing accident. Computer modeling was used to show friction factors. Failure Analysis/Hazard Analysis of Consumer Products Workplace Accident Investigation

    23. Forensic Odontologist (Dentist) Forensic odontology is a specialized field of dentistry which deals with identification of human remains by examining and identifying teeth. Forensic dentist may also participate in mass disaster victim identification, missing persons databases, and bitemark analysis. Forensic odontology is a specialized field of dentistry which deals with identification of human remains by examining and identifying teeth. Forensic dentist may also participate in mass disaster victim identification, missing persons databases, and bitemark analysis.

    24. Forensic Nurse Contrary to popular belief, most forensic nurses dont spend their days hovering over corpses and their nights sleuthing around crime scenes. Instead, they are more likely to spend their hours examining victims of sexual assault or training colleagues how to treat patients injured violently. Forensic nurses responsibilities vary. For example, they may perform death investigations, work with criminals in prison, or counsel schoolchildren who fire guns. Contrary to popular belief, most forensic nurses dont spend their days hovering over corpses and their nights sleuthing around crime scenes. Instead, they are more likely to spend their hours examining victims of sexual assault or training colleagues how to treat patients injured violently. Forensic nurses responsibilities vary. For example, they may perform death investigations, work with criminals in prison, or counsel schoolchildren who fire guns.

    25. Forensic Toxicologist Forensic toxicology is essentially a specialty area of analytical chemistry which specifically looks at body fluids for presence of drugs, poisons, and/or alcohol.Forensic toxicology is essentially a specialty area of analytical chemistry which specifically looks at body fluids for presence of drugs, poisons, and/or alcohol.

    26. Wildlife Forensic Scientist Wildlife forensics is a relatively new field in law enforcement. These are scientists who fight crimes against animals and nature. Wildlife forensics use the same principles as human forensics. The difference is that wildlife forensic scientists need to be able to identify and distinguish between a variety of species--a difficult task. Wildlife forensics is a relatively new field in law enforcement. These are scientists who fight crimes against animals and nature. Wildlife forensics use the same principles as human forensics. The difference is that wildlife forensic scientists need to be able to identify and distinguish between a variety of species--a difficult task.

    27. Here are some forensic science photos--some are from actual crime scenes:

    28. Defense Wounds #1

    29. Defense Wound #2

    30. Defense Posture Such wounds result from an attempt to ward off the assailant. The victim holds up forearms and hands in front of the body. Such wounds result from an attempt to ward off the assailant. The victim holds up forearms and hands in front of the body.

    31. Clay Model Used to Demonstrate Knife Wounds Seen in this clay model is the pattern of a stab wound from a double edge knife on the left and a single edge knife on the right. Seen in this clay model is the pattern of a stab wound from a double edge knife on the left and a single edge knife on the right.

    32. Stab Wound: Single Edge Blade This is a stab wound with a single edge blade. Note the sharp point of the blade at the left and the notch of the opposite side of the knife at the right. The shape of stab wounds can vary considerably, depending upon whether the incision is along the axis of, or perpendicular to, Langer's lines. Those perpendicular will tend to pull apart and gape open, while those parallel to the lines of stress will tend to remain slit-like. This is a stab wound with a single edge blade. Note the sharp point of the blade at the left and the notch of the opposite side of the knife at the right. The shape of stab wounds can vary considerably, depending upon whether the incision is along the axis of, or perpendicular to, Langer's lines. Those perpendicular will tend to pull apart and gape open, while those parallel to the lines of stress will tend to remain slit-like.

    33. Deadly blow to head that resulted in fractured skull and bleeding.

    34. Fractured Liver: Blunt Force Injury Massive abdominal blunt force injury often leads to liver injury, since it is the largest internal organ. Note the multiple lacerations over the capsule. Damage to abdominal organs with lacerations, crush injuries, and rupture can lead to bleeding into the peritoneal cavity known as hemoperitoneum. A peritoneal lavage can detect such bleeding. Massive abdominal blunt force injury often leads to liver injury, since it is the largest internal organ. Note the multiple lacerations over the capsule. Damage to abdominal organs with lacerations, crush injuries, and rupture can lead to bleeding into the peritoneal cavity known as hemoperitoneum. A peritoneal lavage can detect such bleeding.

    35. Natural Death: *Infiltrating Ductal Carcinoma of the Breast *Photographs by Ed Uthman, MD. Public domain. Posted 12 Oct 01 This breast carcinoma, seen here in a mastectomy specimen, is unusually large by today's standards. The tumor measures 5 cm in greatest dimension and extensively involves the nipple (which can be seen as the papillated surface at the top of the specimen. The only way such a superficial tumor can get so large is for the patient to ignore it and not seek medical attention. *Photographs by Ed Uthman, MD. Public domain. Posted 12 Oct 01 This breast carcinoma, seen here in a mastectomy specimen, is unusually large by today's standards. The tumor measures 5 cm in greatest dimension and extensively involves the nipple (which can be seen as the papillated surface at the top of the specimen. The only way such a superficial tumor can get so large is for the patient to ignore it and not seek medical attention.

    36. *Pathologists photo of embryo (ectopic pregnancy) *Photographs by Ed Uthman, MD. Public domain. Posted 12 Oct 01 This photo of an opened oviduct with an ectopic pregnancy features a spectacularly well preserved 10-millimeter embryo. It is uncommon to see any embryo at all in an ectopic, and for one to be this well preserved (and undisturbed by the prosector's knife) is quite unusual. Even an embryo this tiny shows very distinct anatomic features, including tail, limb buds, heart (which actually protrudes from the chest), eye cups, cornea/lens, brain, and prominent segmentation into somites. The gestational sac is surrounded by a myriad of chorionic villi resembling elongate party balloons. This embryo is about five weeks old (or seven weeks in the biologically misleading but eminently practical dating system used in obstetrics). *Photographs by Ed Uthman, MD. Public domain. Posted 12 Oct 01 This photo of an opened oviduct with an ectopic pregnancy features a spectacularly well preserved 10-millimeter embryo. It is uncommon to see any embryo at all in an ectopic, and for one to be this well preserved (and undisturbed by the prosector's knife) is quite unusual. Even an embryo this tiny shows very distinct anatomic features, including tail, limb buds, heart (which actually protrudes from the chest), eye cups, cornea/lens, brain, and prominent segmentation into somites. The gestational sac is surrounded by a myriad of chorionic villi resembling elongate party balloons. This embryo is about five weeks old (or seven weeks in the biologically misleading but eminently practical dating system used in obstetrics).

    37. Forensic Pathologists Tools of the Trade Autopsy tools -- site: http://www.neosoft.com/~uthman/autopsy_tools.html Enterotome These large scissors are used for opening the intestines. The bulb-ended blade is inserted into the lumen (the hollow inside) of the gut, and the instrument is smoothly stripped down the length of the intestine. The blunt bulb keeps the internal blade from perforating the gut from the inside. Skull chisel After scoring the calvarium (the vault-like part of the skull that holds the brain) with the vibrating saw or hand saw, the chisel is used to gently finish the separation of the top of the calvarium from the lower skull, thus exposing the brain and its coverings (meninges). Hagedorn needle Also called the sailmaker's needle, this is a large needle with an eye for sewing up the body after the autopsy is finished. The stitching is similar to that used on the outer covering of baseballs. Heavy twine, which is much coarser than suture, is used for the procedure. Rib cutters These look like small pruning shears and are used to cut through the ribs prior to lifting off the chest plate. Some prosectors actually use pruning shears from a hardware store, which are much less expensive. Scalpel This differs from the surgeon's scalpel in having a longer handle for reaching deeper into body cavities. The disposable blade is usually a #22 size, which is the largest commonly available. Toothed forceps The teeth on these "pickups" lend strength in gripping heavy organs for removal. In surgical pathology, teeth are a liability in that they increase the risk of cross contamination between specimens, so untoothed forceps are used there. Scissors These are otherwise unremarkable scissors used for opening hollow organs (such as the gallbladder) and trimming off tissues. They can also be used for blunt dissection by means of an "opening" motion, rather than the more familiar "closing" motion used in cutting. Bone saw This hand saw is rarely used today, most often by pathologists who fear infection from aersols thrown up by the much more vigorous vibrating saw (see below). The hand saw can be used to saw through the skull, but it's very slow-going compared to the vibrating saw.Autopsy tools -- site: http://www.neosoft.com/~uthman/autopsy_tools.html Enterotome These large scissors are used for opening the intestines. The bulb-ended blade is inserted into the lumen (the hollow inside) of the gut, and the instrument is smoothly stripped down the length of the intestine. The blunt bulb keeps the internal blade from perforating the gut from the inside. Skull chisel After scoring the calvarium (the vault-like part of the skull that holds the brain) with the vibrating saw or hand saw, the chisel is used to gently finish the separation of the top of the calvarium from the lower skull, thus exposing the brain and its coverings (meninges). Hagedorn needle Also called the sailmaker's needle, this is a large needle with an eye for sewing up the body after the autopsy is finished. The stitching is similar to that used on the outer covering of baseballs. Heavy twine, which is much coarser than suture, is used for the procedure. Rib cutters These look like small pruning shears and are used to cut through the ribs prior to lifting off the chest plate. Some prosectors actually use pruning shears from a hardware store, which are much less expensive. Scalpel This differs from the surgeon's scalpel in having a longer handle for reaching deeper into body cavities. The disposable blade is usually a #22 size, which is the largest commonly available. Toothed forceps The teeth on these "pickups" lend strength in gripping heavy organs for removal. In surgical pathology, teeth are a liability in that they increase the risk of cross contamination between specimens, so untoothed forceps are used there. Scissors These are otherwise unremarkable scissors used for opening hollow organs (such as the gallbladder) and trimming off tissues. They can also be used for blunt dissection by means of an "opening" motion, rather than the more familiar "closing" motion used in cutting. Bone saw This hand saw is rarely used today, most often by pathologists who fear infection from aersols thrown up by the much more vigorous vibrating saw (see below). The hand saw can be used to saw through the skull, but it's very slow-going compared to the vibrating saw.

    38. Hammer with hook The hammer (perhaps the Beatles' inspiration for "Maxwell's silver hammer"?) is used with the chisel to separate the calvarium from the lower skull. The hook is handy to pull the calvarium away. Breadknife Also referred to simply as the "long knife," this is used to smoothly cut solid organs into slices for examination, display, and photography of the organs' cut surfaces. Particularly facile prosectors pride themselves on being able to do almost all of the soft tissue dissections (including stripping the gut from the mesentery and opening the heart chambers) with this large, unlikely-looking blade. The example shown here includes a disposable blade. Models with permanent, resharpenable blades are also available. Hammer with hook The hammer (perhaps the Beatles' inspiration for "Maxwell's silver hammer"?) is used with the chisel to separate the calvarium from the lower skull. The hook is handy to pull the calvarium away. Breadknife Also referred to simply as the "long knife," this is used to smoothly cut solid organs into slices for examination, display, and photography of the organs' cut surfaces. Particularly facile prosectors pride themselves on being able to do almost all of the soft tissue dissections (including stripping the gut from the mesentery and opening the heart chambers) with this large, unlikely-looking blade. The example shown here includes a disposable blade. Models with permanent, resharpenable blades are also available.

    39. Stryker Saw: good for cutting into skull Vibrating saw The vibrating saw, also referred to eponymously as the "Stryker saw," is the instrument of choice for most prosectors faced with removing the brain. The blade reciprocates rapidly with a small amplitude. This action prevents the saw from cutting soft tissues, notably the prosector's hand. The disadvantage of vibrating saws is that they throw up more potentially infectious aerosols than do hand saws. Vibrating saw The vibrating saw, also referred to eponymously as the "Stryker saw," is the instrument of choice for most prosectors faced with removing the brain. The blade reciprocates rapidly with a small amplitude. This action prevents the saw from cutting soft tissues, notably the prosector's hand. The disadvantage of vibrating saws is that they throw up more potentially infectious aerosols than do hand saws.

    40. Digital Imagery Reconstruction: Use of computer superimposes photo of skull with outer skin. Computer imagery is helping forensic scientist identify skeletal remains.Computer imagery is helping forensic scientist identify skeletal remains.

    41. Facial reconstruction technique used by forensic artists.

    42. Some forensic scientists participate in high profile cases and become famous.

    43. Meet Dr. Henry Lee--one of the worlds most renowned forensic pathologists. This legendary investigator is known for finding the tiniest clues, and has once solved a murder without a body. He is one of Americas foremost crime scene experts and has worked on many high profile cases including: O.J. Simpson, JonBenet Ramsey, and William Kennedy Smith. Lee began his career in Taiwan as a police officer. His first homicide case was a dismembering case. He recalls, For a month, I didnt want to eat meat. I almost became a vegetarian. Lee came to New York in 1965. He remembers that he only had about $50. In his pocket and knew about three words of English. Ten years later, he had a doctorate degree in biochemistry and was running a small forensics department. Lee is methodical and patient in his endeavors to solve crimes. One of Lees colleagues stated that Lee always insisted on going to the scene of the crime himself. His colleague remembers that Lee once asked him to bite his own tissue and then examine the mark to learn about the healing process! This legendary investigator is known for finding the tiniest clues, and has once solved a murder without a body. He is one of Americas foremost crime scene experts and has worked on many high profile cases including: O.J. Simpson, JonBenet Ramsey, and William Kennedy Smith. Lee began his career in Taiwan as a police officer. His first homicide case was a dismembering case. He recalls, For a month, I didnt want to eat meat. I almost became a vegetarian. Lee came to New York in 1965. He remembers that he only had about $50. In his pocket and knew about three words of English. Ten years later, he had a doctorate degree in biochemistry and was running a small forensics department. Lee is methodical and patient in his endeavors to solve crimes. One of Lees colleagues stated that Lee always insisted on going to the scene of the crime himself. His colleague remembers that Lee once asked him to bite his own tissue and then examine the mark to learn about the healing process!

    44. The Inspector hopes you enjoyed learning about the world of forensic science.

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