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NCJ Number: 200123 Find in a Library
Title: Crash Reconstruction Basics for Prosecutors: Targeting Hardcore Impaired Drivers
Corporate Author: American Prosecutors Research Institute
United States of America
Date Published: March 2003
Page Count: 33
Sponsoring Agency: American Prosecutors Research Institute
Alexandria, VA 22314
Sale Source: American Prosecutors Research Institute
99 Canal Center. Plaza
Suite 510
Alexandria, VA 22314
United States of America
Type: Program/Project Description
Format: Document
Language: English
Country: United States of America
Annotation: This document provides information to prosecutors on the basic science, investigative techniques, and questions to ask on crash reconstruction.
Abstract: Evaluating fatal motor vehicle crashes is one of the more difficult challenges for prosecutors. Roughly 40 percent of all the fatal crash reports that prosecutors assess will involve impaired driving. After a crash, the prosecutor receives a written police report, and in many cases, a part of that report focuses on the reconstruction of the crash. The prosecutor can strengthen the investigation by critically assessing the reconstruction and playing the role of the devil’s advocate. Challenging questions must be asked. The prosecutor should be particularly sensitive to issues affecting the credibility of the potential police witness at trial. It is important for prosecutors to visualize the crash from the information in the report alone. Searching for gaps in the paperwork may suggest reasonable doubt later. Prosecutors often make the mistake of taking for granted proof of operation. The anatomy of a crash is composed of three chronological phases -- pre-impact, impact (engagement), and post-impact. Reconstruction fundamentals include energy analysis (motion energy), an analysis of speed from friction marks made by tires, and measurement with a drag sled (an accelerator attached to a vehicle). Since the drag factor is an important part of the reconstruction methodology, defense attacks attempt to lower the value measured at the scene by investigators. The length of a braking action is determined by the measurements of the tire marks on the roadway. Another method used to determine pre-impact speed is based upon the principle of conservation of momentum. The level of defense attack on the prosecution’s reconstruction is inversely proportional to the level of completeness of the prosecution’s investigation. Errors or omissions in scene processing, examining the vehicles, taking witness statements, and reconstructing the events provide attack points for the defense. The key to handling the adverse expert is preparation. 13 endnotes
Main Term(s): Accident investigation; Prosecutors
Index Term(s): Court procedures; Investigative powers; Prosecution; Prosecutor training; Reckless driving; Skid marks; Traffic accidents
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