PPT-Unit 5: Firearms, Tool Marks, and Other Impressions

Mr Ross Brown Brooklyn School for Law and Technology How can we determine the firearm from which a bullet was shot 18 April 2016 Do now What makes it difficult to determine which firearm shot a specific bullet. Tim Counce. Forensic Scientist IV. Purpose: To provide members of the legal community the scientific underpinnings of forensic firearm and toolmark analysis, its compliance with applicable scientific criteria for admission under Daubert and Frye standards, and associated published research substantiating the discipline. Impressions rather than standard impressions, advertisers cut out risk of wasted spend on unseen ads or fraudulent impressions. engage:BDR’s Viewable Impressions boast high engagement and perfor , Tool Marks, and Other Impressions. Bullet and Cartridge Comparisons. Gun Barrel-1. Rifling-impressing of the inner surface of a gun barrel with spiral grooves.. Imparts spin to projectile to keep it on course. Tool marks. Chapters 15 & 16. PVMHS. , 2015. Student objectives:. Distinguish between patent, latent, and plastic impressions . Describe how to make foot, shoe, and tire impressions . Use track width and wheel base information to identify vehicles . Tooth Mark Comparisons. Forensic Science . 4/28/14. Drill. What is the top part of the jaw called? The bottom part?. What are two reasons why a bite might be a better form of identification than a fingerprint?. Types of impressions. Patent Impressions- Visible, two dimensional impressions produced as an object moves through soil, dust, paint, blood, or other fine particles. Latent impressions- hidden to the eye, but can be visualized through the use of special dusting and electrostatic techniques or chemical developers.. Forensic Science . 4/28/15. Pd. 3 . If you did not take the quiz yesterday, grab two yellow folders, drop off your phone, and move to one of the back tables, around the wall.. During the drill, Ms. Bloedorn will bring you . Forensic Science. 2. Copyright and Terms of Service. Copyright © Texas Education Agency, 2011. These materials are copyrighted © and trademarked ™ as the property of the Texas Education Agency (TEA) and may not be reproduced without the express written permission of TEA, except under the following conditions:. Chapter 15. Introduction. Structural variations and irregularities caused by scratches, nicks, breaks, and wear may permit the criminalist to relate: . A bullet to a gun. A scratch or abrasion mark to a single tool. September 29. , 2014. How can footwear evidence be used to solve crimes?. Identification of a suspect (more on this later!). Number of . perpetrators. Location of prints may help reconstruct crime. Confirm / rebut alibis or witness statements. The Chinese invented gunpowder over a thousand years . ago. . using KNO. 3. , charcoal and sulfur.. Muzzle-loading matchlocks used wicks to ignite the gunpowder. . The cartridge and breech loading followed. . Chapters 15 & 16. PVMHS. , 2015. Student objectives:. Distinguish between patent, latent, and plastic impressions . Describe how to make foot, shoe, and tire impressions . Use track width and wheel base information to identify vehicles . : when tool is pressed into soft material. Show outline of tool. Sliding. : when tool is slides across the surface. Has a pattern of parallel striations. Class characteristics are hard to determine because many tools make similar sliding marks . What is AO1?. Demonstrate knowledge and understanding of scientific ideas, processes, techniques and procedures.. You usually need . to have . learnt. work to answer AO1 questions. Recall of facts. simple e.g. test for oxygen gas.