Unit 3 Creative Project
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1. Physical evidence like fingerprints, firearms, trace evidence, and biological evidence can be used to identify suspects and link them to crimes. This evidence is collected using techniques like dusting for fingerprints, and DNA testing of biological samples. 2. Once collected, evidence is examined using specialized equipment like microscopes, chemicals, and DNA testing to analyze samples and identify their characteristics. 3. Evidence can provide critical information to investigations by identifying suspects and objects, reconstructing crimes, and exonerating the innocent when analyzed properly. Contamination issues need to be avoided during the collection and examination of evidence.
Unit 3 Creative Project
- 1. Evidence and It's Importance Unit 3 Creative Project Elizabeth Hall Kaplan University CJ210 Criminal Investigation Joseph Reynolds November 3 2009 Gathering Fingerprint Evidence
- 2. Question What are the main types of evidence, and what is their importance to the investigative process? Crime Scene Tool Kit
- 3. Types of Evidence, and the Techniques Used for Collection Evidence is predominantly grouped into two categories which can then be broken down into subgroups: Physical Evidence also known as "real evidence.- "Locard's Exchange Theory: every contact leaves a trace". (DNA Initiative, 2008) Testimonial Evidence is statements, or oral facts given to investigators by witnesses, informants, or victims. Evidence Collection ID Tag
- 4. Types of Evidence, and the Techniques Used for Collection Continued Physical Evidence Fingerprints- Collected with a variety of tapes, powders, chemicals, and glues using the contrast technique. Firearms- Bullet casings, striation marks and spent cartridges, these are collected with tweezers and sealed in an evidence container Trace Evidence- Hairs, fibers, and particulate material, collected by shaking, sifting, tape lifting, or vacuuming. Fingerprint- Green Magnetic Powder
- 5. Types of Evidence, and the Techniques Used for Collection Continued 2 Physical Evidence 2 Biological evidence- Document evidence- Letters, papers, handwriting samples collected, and sealed in evidence containers Physical evidence, properly collected, documented, and analyzed is: more reliable than testimonial evidence, known as the silent witness can corroborate witness statements help investigators reconstruct the crime is completely objective can help to prove or disprove innocence. (DNA Initiative. (2008)) Biological Specimen Kit
- 6. Types of Evidence, and the Techniques Used for Collection Continued 3 Testimonial Evidence Testimonial evidence includes signed statements, videos, and audio recordings. Can be gathered in various places, for example: the police station, a person's home, a hospital, or anywhere an officer can talk to or ask a person questions. Is collected with the use of paper, pens, video equipment, or audio equipment. Photographic Barrier Filter
- 7. Evidence Examination Once evidence is collected, it must be developed and examined using various types of equipment and chemicals. Fingerprints-developed and examined using the contrast method, and fuming methods, comparison to known prints, and fingerprint microscopes. Firearms and tool striations- developed and examined using morphology, spectrophotometers, mass spectrographs, and various magnifying instruments Trace Evidence- developed and examined using tapes, filters, spectrometers, high resolution lenses, various microscopes, spectrographs, x-ray diffraction, neutron activation, and chromatography instruments Cyanoacrylate Fuming Chamber
- 8. Evidence Examination 2 Biological evidence is developed and examined in different ways depending on the material DNA- short tandem repeat (STR) testing Blood- Leuco-Malachite Green Test, Luminol, Reduced Phenolphthalein Test, Tetramethyl Benzidine Test, Hemin Crystal Test, Precipitin Test, Blood Group Test, and DNA tests, Spatter Trajectory Tests Biological evidence can definitively tie a suspect to a crime, since no two person's DNA is the same with the exception of some twins. Blood Spatter Tool Kit
- 9. Evidence Examination 3 Document Evidence is developed and examined in numerous ways, by experts in forgery, handwriting, fingerprints, paper, and ink, using fuming, microscopes, magnifiers, chemicals, spectrometers, chromatographs, and spectrophotometers Testimonial evidence is examined with polygraph tests, voice analysis, body language, and the skills developed by the investigator. Fingerprints-Check developed with Ninhydrin
- 10. Information from Evidence Information found through investigation can: "Identify a substance, object, or instrument" "Link suspect to crime and or victim" "Reconstruct the crime" "Protect the innocent" "Provide expert testimony" (Osterburg & Ward 2007) Fingerprints- can definitively identify a suspect, and place them at the scene of the crime because no two people have the same fingerprint whirls, arches, loops, dots, ridge endings, bifurcations, short ridges, enclosures, bridges, spurs, or trifurcation ridge endings Firearms, shoes, and tools develop individualized striations from use or manufacture that can positively identify them as being at the scene, or help to reconstruct the scene using morphology Fingerprint- Orange Fluorescent Fingerprint Powder
- 11. Contamination Issues The rules of Locard's Law applies to everyone, not just suspects, victims and witnesses Environmental issues such as rain, heat, wind can contaminate or cause the evidence to erode, deteriorate, or disappear For witness corroboration, people can forget details Too many people in the crime scene area Improper packaging or storage Tamper Resistant Evidence Bag
- 12. Relevant Issues The sciences of evidence have come a long way in a few short years. While there are still issues concerning the reliability of the science behind the results, the advanced use of science has proved to be an invaluable tool in the protection of those who are innocent Wheel used to mark off crime scene
- 13. References The DNA Initiative. (2008). Crime Scene and DNA Basics for Forensic Analysis Retrieved from the World Wide Web October 30, 2009 http://dna.gov/training/evidence Evident Crime Scene Products (2009) Quality Products Delivered. Retrieved from the World Wide Web October 30, 2009. http://www.evidentcrimescene.com/cata/photo/photo.html Osterburg and Ward. (2007). Criminal Investigation: A Method for Reconstructing the Past. Fifth Edition. Pages 25 – 106. Copyright © 2007 Matthew Bender & Company, Inc. Licensed to Kaplan University in Agreement with LexisNexis Anderson Publishing www.shutterstock.com- 93154 (n.d.) Chalk Body Outline Retrieved from the World Wide Web October 30, 2009 Michael Jackson (2006) Smooth Criminal. Smooth Criminal albumn released 2006 Shoeprint lifted with gel
Editor's Notes
- #4: Locard's theory applies to all people in the crime scene, emergency personnel, medical personnel, police officers, witnesses, victims, and animals.
- #5: If evidence is not properly documented with the chain of custody, it will not be admissible
- #6: Where testimonial evidence can be forgotten or altered physical evidence and science are not usually disprovable.
- #7: Testimonial evidence is best when corroborated with physical evidence
- #8: The professionals who examine and document this evidence also can serve as expert witnesses
- #9: The examination of blood spatter can reconstruct the events of the crime
- #10: Document evidence is helpful in cases of fraud, theft, kidnapping, robberies, among other things
- #11: Physical evidence reports are useful in the interrogation stage of an investigation as well
- #12: Any of these contamination issues can cause the evidence to become inadmissible in court.