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An Introduction to Forensic Science

An Introduction to Forensic Science. Powerpoint used an altered: Original belongs to South Pointe High School. What is Forensic Science?. Forensic science is the application of scientific knowledge to questions of civil and criminal law(legal stuff). Also called Criminalistics.

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An Introduction to Forensic Science

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  1. An Introduction to Forensic Science Powerpoint used an altered: Original belongs to South Pointe High School

  2. What is Forensic Science? • Forensic science is the application of scientific knowledge to questions of civil and criminal law(legal stuff). Also called Criminalistics

  3. Areas of Forensic Science

  4. Course Topics & Perspective • Forensic scientists are also required to testify in court about their analysis of evidence. • To make a convincing case, you need to be able to clearly and concisely explain your results and their significance in lab reports. • Finally, mock crime scenes will be investigated and real case studies analyzed.

  5. Interdisciplinary Relationships • Forensics is a diverse field, and rarely are forensic scientists “generalists” – people who specialize in all aspects of forensic science. Forget what you see on CSI. • Forensic scientists don’t wear pumps to a crime scene, they rarely interview suspects or make arrests, and they are not experts in all areas of forensic investigations. Rather, forensic experts usually specialize in one or two branches of forensic investigation.

  6. Interdisciplinary Relationships • A botanist may be an expert in forensic botany. An entomologist may be an expert in forensic entomology. Chemists may specialize in forensic toxicology or arson and bomb analysis. People with expertise in physics may focus on firearms and ballistics or blood spatter analysis.

  7. Interdisciplinary Relationships • It would be impossible to survey all areas of forensic science in a semester long high school course. • Rather, we will explore a range of fields, topics and methodologies to give you a sense of the diverse fields of study in forensics.

  8. Interdisciplinary Relationships • Nevertheless, forensic science is an applied scientific discipline, and your success in this course will require you to apply your basic understanding of physics, chemistry, biology and even math to explore the range of topics surveyed.

  9. Why do we look to science for assistance in our legal system? • Increasing Crime Rates • New or Changed Laws • New Crimes • New Weapons (*see next slide) • Response to Public Concerns • Response to Law Enforcement Concerns

  10. New Weapons?

  11. Applying Science to Law • Applying science to the Criminal Justice System depends on a scientist’s ability to supply accurate & objective information that reflects the events that have occurred at a crime.

  12. Civil vs. Criminal Law

  13. History & Development of Forensic Science

  14. When in Rome… • “Forensic” comes from the Latin word “forensis” meaning forum. • During the time of the Romans, a criminal charge meant presenting the case before the public. • Both the person accused of the crime & the accuser would give speeches based on their side of the story. • The individual with the best argument would determine the outcome of the case.

  15. Sir Arthur Conan Doyle • Mystery author in late 1800’s • Popularized scientific crime-detection methods through his fictional character ‘Sherlock Holmes’.

  16. Mathieu Orfila(1787-1853) • “Father of Toxicology” • Wrote about the detection of poisons & their effects on animals.

  17. Alphonse Bertillon(1853-1914) • “Father of Anthropometry” • Developed a system to distinguish one individual person from another based on certain body measurements.

  18. Anthropometry

  19. Francis Galton(1822-1911) • “Father of Fingerprinting” • Developed fingerprinting as a way to uniquely identify individuals.

  20. Leone Lattes(1887-1954) • “Father of Bloodstain Identification” • He developed a procedure for determining the blood type (A, B, AB, or O) of a dried blood stain.

  21. Calvin Goddard(1891-1955) • “Father of Ballistics” • Developed the technique to examine bullets, using a comparison microscope, to determine whether or not a particular gun fired the bullets.

  22. Albert Osborn(1858-1946) • “Father of Document Examination” • His work led to the acceptance of documents as scientific evidence by the courts.

  23. Walter McCrone(1916-2002) • “Father of Microscopic Forensics” • He developed & applied his microscope techniques to examine evidence in countless court cases.

  24. Hans Gross(1847-1915) • “Father of Forensic Publications” • Wrote the book on applying all the different science disciplines to the field of criminal investigation.

  25. Edmond Locard(1877-1966) • “Father of the Crime Lab” • In 1910, he started the 1st crime lab in an attic of a police station in Paris, France. • With few tools, he quickly became known world-wide to forensic scientists & criminal investigators & eventually founded the Institute of Criminalistics in France. • His most important contribution was the “Locard’sExchangePrinciple”

  26. Locard’s Exchange Principle • “Every Contact Leaves a Trace.” • He believed that every criminal can be connected to a crime by particles carried from the crime scene. • When a criminal comes in contact with an object or person, a cross-transfer of evidence occurs.

  27. J. Edgar Hoover • “Father of the FBI” - Director of Federal Bureau of Investigation during the 1930’s • Hoover's leadership spanned 48 yrs & 8 presidential administrations. His reign covered Prohibition, the Great Depression, WWII, the Korean War, the Cold War, & the Vietnam War. • He organized a national laboratory to offer forensic services to all law enforcement agencies in the U.S. • VERY CONTROVERSIAL • He exceeded & abused his authority with unjustified investigations & illegal wiretaps based on political beliefs rather than suspected criminal activity • FBI directors are now limited to 10-year terms

  28. Applications of Forensic Science • Identification of Criminals or Victims • Solving Mysteries • Past crimes (unsolved or wrongfully convicted) • Cause, Location, Time of Death • Paternity cases • Cyber crimes • Corporate Crimes (Enron) • Voice Analysis

  29. Applications of Forensic Science • Application of DNA as evidence • Prevention vs. Reaction • Catastrophes & Wars • ID remains of victims (either civilian or soldiers) • ex. Holocaust or Katrina • Military & International Forensics • Terrorism • The search for WMD’s • stockpiled or stored weapons from past wars

  30. Forensic Scientist Job Description • Process and document crime scenes • Collect and preserve evidence • Analyze and compare evidence in a laboratory • Reconstruction of data • Provide Expert Testimony Skills Needed • Good observation skills • Analytical skills • Deductive reasoning

  31. Branches of Forensic Science: • medical doctors, medical examiners, and pathologists • study medical history, perform an autopsy, and collect medical and trace evidence from the body for further analysis • Help determine cause and circumstances of death

  32. dentists who specialize in identification perform bite mark analysis and dental identification when there is no other way for body identification

  33. Forensic Toxicology • medical examiners and the Coroner’s office determine toxic substances in the body; includes drugs and poisons

  34. Forensic Anthropology • identification of persons or personal characteristics (sex, age, race, stature) based on body remains

  35. When the Army unearthed more than a 1,000 mortar rounds from a WW2 training site, they enlisted a Forensic Science Lab to determine which were live munitions & which were dummies. Munitions

  36. Forensic Serology • identification of blood and other body fluids (semen, vaginal fluid, saliva)

  37. Forensic Serology • identification of blood and other body fluids (semen, vaginal fluid, saliva)

  38. Forensic Psychiatry and Psychology • evaluate offenders and profile criminal cases

  39. Forensic Computer Science • investigate criminal use of technology and electronic records

  40. Forensic Entomology • uses insects to determine time of death and location of a corpse

  41. Changes Induced at Scene and Physical Evidence • We cannot stress how much any find at a crime scene is important. • A single bead of a necklace can be the determining factor of trying to prove someone's whereabouts.

  42. Imprints vs Indentations • An imprint is a mark left by an object when it came in contact with another object (2D) • An indentation is a three-dimensional mark left in a soft(derformable) object.

  43. Striations • Grooves/Scratches when two surface pass over each other. (Toolmarks)

  44. Locard Exchange Principle • Another way physical evidence is produced is when two surface/materials come into contact. • There will be an exchange of material across the contact boundary. • Example: animal hair.

  45. Deposits • Sometimes direct contact is not required. Physical evidence can be left behind when large or small quantities of materials travel through the air.

  46. Uses of Physical Evidence • Developing an MO (Modus Operandi) • https://www.psychologytoday.com/blog/shadow-boxing/201312/serial-killer-signatures • https://www.instantcheckmate.com/crimewire/post/worst-serial-killers/ • Looking through physical evidence allows to determine commonalities among crime scenes.

  47. Exclusions and Linkages • Proving something DOESN’T belong to a crime is as powerful as proving something DOES belong. • The goal is corpus delecti - the facts and circumstances constituting a breach of a law. • concrete evidence of a crime, such as a corpse. • Linkage shows events are linked, exlusionsshows events are not.

  48. Importance of Proper Evidence Collection You can be the smartest scientist in the world but improper handling of evidence can break a case.

  49. Chain of Custody: • Chain of Custody refers to the document or paper trail showing the seizure, custody, control, transfer, analysis, and disposition of physical and electronic evidence. • Chain-of-custody bears on the weight of the evidence, not its admissibility. • Just because you don’t have a chain-of-custody process doesn’t mean that the evidence is inadmissible. Admissibility is determined by the manner in which the evidence was acquired. It must be legally obtained!

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