1 / 18

Introduction to Forensic Science

Introduction to Forensic Science. Forensic Science. Involves the application of scientific theory, process, and techniques in legal matters. Primary role of a forensic scientist is to analyze evidence gathered at a crime scene. Science Disciplines Needed. Biology Physics Geology

yosefu
Download Presentation

Introduction to Forensic Science

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Forensic Science

  2. Forensic Science • Involves the application of scientific theory, process, and techniques in legal matters. • Primary role of a forensic scientist is to analyze evidencegathered at a crime scene.

  3. Science Disciplines Needed • Biology • Physics • Geology • Anthropology • Psychiatry • Photography • Toxicology • Ballistics • Odontology (in forensics: examination of bite marks and dental identification of corpses) • Engineering • Chemistry • Computer technology • Pathology (investigation of a sudden, unexplained death) • Environmental science • Entomology (study of insects, particularly decomposers in forensics) • Palynology (study of pollen and spores) • Polygraphy(use of lie detectors)

  4. Locard’s Exchange Principle • Edmond Locardwas a pioneer in the field of forensic science. • He became known as “The Sherlock Holmes of France.” • In 1910, when he opened his forensic lab, he stated that whenever an individual comes in contact with a crime scene or victim, there will be an exchange of materials between them.

  5. Two Types of Evidence • Testimonial evidence:prima facie evidence or direct evidence, a statement made by a competent witness under oath. • Physical evidence: real evidence; any object or material relevant to a crime.

  6. Example of Physical Evidence • Hair, fibers, soil, glass, body fluids, fingerprints, pollen, bones, toxic substances, documents, firearms, ammunition, gunshot residues and impressions (bite marks, shoeprints, etc.)

  7. Types of Physical Evidence • Individual: linked to a single source • Examples: fingerprints and footprints • Class: Material that can be linked to only a group of items with similar properties • Examples: hair and blood type

  8. Two Forms of All Evidence • Both testimonial or physical evidence can be either direct or circumstantial evidence. • Direct evidence: links the suspect to the crime • Examples: blood alcohol content or possession of an illegal substance • Circumstantial evidence: points to a possibleconnection between the evidence and the suspect

  9. Forensic Evidence Databases • The National Integrated Ballistics Information Network (NIBIN) allows the comparison of markings made by a firearm on bullets and cartridge casings. • The International Forensic Automotive Paint Data Query (PDQ) contains chemical and color information pertaining to original automotive paints. • SICAR (shoeprint image capture and retrieval) is a shoeprint database. • TheIntegrated Automated Fingerprint Identification System (IAFIS), a national fingerprint and criminal history system maintained by the FBI. • The Combined DNA Index System (CODIS) enables federal, state, and local crime laboratories to electronically exchange and compare DNA profiles.

  10. The Crime Scene • Forensics begins at the scene of the crime. • Careful, objective, and scientific treatment of all evidence must occur. • If not, vital evidence may be overlooked, damaged, or contaminated; making it useless in a court of law.

  11. Primary CSI Procedures • Interview • Examine • Photograph • Sketch • Process • Tag all evidence with a number. • Photograph it. • Package it. • Label it.

  12. Notes • Police notes begin with your assignment to the case and continue to the end of the investigation. • Supplement all photos, sketches, and scale drawings. • Print with a smudge-proof blue or black ink. • Number and identify each page with your name, title, case number, and date. • Record the time an action was taken, information received, or event was observed. • Do not edit or erase. Line out the entry, initial, and rewrite.

  13. Forensic Photography • No objects are removed until they have been photographed from all necessary angles. • Three ranges of picture documentation: • Overview • Intermediate • Close-up (close and perpendicular to the object.)

  14. Photo Log Information • Assign each photo a number. • Describe photo contents. • Cite the time the photo was taken, the type of photo, and the distance to the focal point. • List the type of camera used and the height at which it was held.

  15. Additional Photo Log • List the position of the camera or the angle of the camera shot. • List what lens was used; whether a flash was used; and whether digital or the type of film. • If film, note when new film is loaded. • Note all data on a photo sketch, as well as in your notes.

  16. Crime Scene Sketches • Aerial view of the entire crime scene • Rough sketch vs. finished drawing

  17. Elements of Sketching • Measurements • Compass directions • Essential items • Scale or proportion • Legend • Title (case-file # and offense) • Projection • Surveying methods • Rectangular (hypotenuse) or polar coordinates (length and angle.)

  18. Projection Drawing • Looks like a box with all four sides flattened.

More Related