Speed Estimates from Braking Evidence

This course is accredited for 6.0 hours of continuing education credits by Missouri POST.

To successfully investigate a vehicle crash, officers must be able to analyze tire mark evidence. Through video lectures from a motor vehicle crash expert, this course examines the science that supports speed estimates from braking evidence. Course topics include:

Fundamentals of speed from tire mark evidence, including skid and ABS tire marks
Extensive discussion about drag factor measurements, including drag sled and accelerometer measurements, and a discussion of potential accelerometer misuse
The speed-from-skid equation, with explanations about the input variables, with extensive comments about braking efficiency considerations
Potential challenges on the evidence, with the necessary background for defending the evidence against unfair attacks at trial

With clear, easy-to-understand explanations that build credibility for the officer when integrated into trial testimony, the course includes numerous examples and analogies to help officers better and understand significant scientific concepts. All materials are delivered with an emphasis on “plain speak,” a signature of Prof. Kwasnoski’s presentation style. The successful investigation and prosecution of a motor vehicle crash may include issues that are not part of the ordinary at-scene checklist of evidence, and this course provides critical concepts to help officers employ scientific principles in furtherance of their investigations.

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About the Instructor

Professor John Kwasnoski

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John B. Kwasnoski is Professor Emeritus of Forensic Physics at Western New England University, Springfield, MA after thirty-one years on the faculty. He is a certified police trainer in more than twenty states, and has instructed prosecutors, police, and civil attorneys on more than 330 occasions across the U.S. He is the crash reconstructionist on the “Lethal Weapon – DWI Homicide” team formed by the National Traffic Law Center to teach prosecutors how to utilize expert witness testimony and cross examine adverse expert witnesses.

Prof. Kwasnoski has reconstructed more than 1,300 crashes since 1985, including multiple and single vehicle, pedestrian, motorcycle, and train crashes, and has given sworn testimony on more than 200 occasions; he has trained with the NYPD collision reconstruction unit since 2001, and continues to serve as a consultant to prosecutors nationwide on MV homicide cases. He has worked for more than twenty major insurers as a consultant/expert witness, and has conducted training for the claims adjusters and special investigators of a number of insurance companies.

He has served as an expert in several cases of national significance including S. Carolina v. Susan Smith (a mother’s drowning murder of her two children) in which he participated in the re-enactment of the drowning in a submerged automobile and the creation of a video used in the sentencing phase of the trial. He was the reconstructionist for the plaintiff in the case of Ulm v. Ford Motor Co. in which a Vermont jury awarded the plaintiff more than one million dollars.

Prof. Kwasnoski has authored The Handbook of Collision Reconstruction, Kwasnoski’s Little Red Book, and Crash Reconstruction Basics for Prosecutors, and has co-authored three best-selling books for Lexis Law Publishing : Investigation and Prosecution of DWI and Vehicular Homicide, Courtroom Survival, and The Officer’s DUI Manual. Prof. Kwasnoski has published more than 80 journal and newsletter articles on collision reconstruction, and maintains an active national speaking schedule; find out more at www.legalsciences.com.