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2009©Forensic Science Today Hair Evidence
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2009©Forensic Science Today Parts of the Hair Medulla Cuticle Cortex Follicle Root Distal end Proximal end
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2009©Forensic Science Today Medulla Types Intermittent Fragmented continuous
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2009©Forensic Science Today Medullas Hair in top image- uniserial ladder medulla pattern Hair in top image- uniserial ladder medulla pattern Hair in middle image- multiserial ladder medulla pattern Hair in middle image- multiserial ladder medulla pattern Hair in bottom image- deer medula Hair in bottom image- deer medula Deedrick, D. W. Hairs, fibers, crime, and evidence, Forensic Science Communications [Online]. (Jan 2004). Available: http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm
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2009©Forensic Science Today Cuticle Types Coronal mouse Imbricate human Spinous cat Deedrick, D. W. Hairs, fibers, crime, and evidence, Forensic Science Communications [Online]. (Jan 2004). Available: http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm.http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm
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2009©Forensic Science Today Human Cuticle Deedrick, D. W. Hairs, fibers, crime, and evidence, Forensic Science Communications [Online]. (Jan 2004). Available: http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm.http://www.fbi.gov/hq/lab/fsc/backissu/jan2004/deedrick.htm
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2009©Forensic Science Today Medullary Index Width of the medulla/ width of the hair shaft Width of the medulla/ width of the hair shaft If it is less than 1/3, it is human If it is less than 1/3, it is human
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2009©Forensic Science Today Cortex Contains pigment granules. Contains pigment granules. Pigment distribution Pigment distribution Dyed hair Dyed hair Undyed hair Undyed hair Undeveloped or missing pigments cause grey hair Undeveloped or missing pigments cause grey hair
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2009©Forensic Science Today Proximal End End nearest torso End nearest torso Root or no root? Root or no root?
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2009©Forensic Science Today Distal End End farthest from the torso End farthest from the torso
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2009©Forensic Science Today Telogen, Anagen & Categen Phases of Hair
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2009©Forensic Science Today Observe Cuticle Type of cuticle Type of cuticle Is this possibly human? Is this possibly human? Damaged or undamaged Damaged or undamaged
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2009©Forensic Science Today Questions About Hair All hair on one head the same? All hair on one head the same? Different on different body areas? Different on different body areas? Tell race of person from hair? Tell race of person from hair? Sex of person from hair? Sex of person from hair? Age of person from hair? Age of person from hair?
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2009©Forensic Science Today Comparing Hair Samples? Comparing hair from a scene to hair from a known source? Comparing hair from a scene to hair from a known source? Is it Similar? What makes it Similar? Is it Similar? What makes it Similar? All the characteristics found on the known hair and the questioned hair must be identical. All the characteristics found on the known hair and the questioned hair must be identical. What does it mean to say they are consistent with one another? What does it mean to say they are consistent with one another?
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2009©Forensic Science Today Class vs. Individual Hair has basically class characteristics Hair has basically class characteristics Matching distribution of pigment, medulla type and cuticle type can be found in many individuals. Matching distribution of pigment, medulla type and cuticle type can be found in many individuals. Cellar material present Cellar material presentDNA???
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2009©Forensic Science Today Hair Collection Cellophane tape into Petri dish or Cellophane tape into Petri dish or Vacuuming Vacuuming Choose container that will prevent loss Choose container that will prevent loss Label and Label and Seal Seal Receipt for evidence!!! Receipt for evidence!!!
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2009©Forensic Science Today Control Samples Determine the source of evidence Determine the source of evidence Uncontaminated Uncontaminated From known source From known source For hair-must be pulled For hair-must be pulled 50 from all over head 50 from all over head 24 from pubic area in case of sexual assault 24 from pubic area in case of sexual assault
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