What Does Traffic Collision Reconstruction Mean

What Does Traffic Collision Reconstruction Mean?

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Traffic crash reconstruction is a scientific technique for determining a collision’s conditions, mechanics, and contributing variables.

It calls for practical expertise in various fields, such as physics, vehicle dynamics, mathematics, photogrammetry, and computer skills (i.e., spreadsheets, AutoCAD, simulation or modeling tools, graphics, and photo-management software). 

After carefully assessing the available evidence, the reconstructionist can answer questions like “How fast was the vehicle moving at the time of impact?”, “How much did the vehicle slow during the locked-wheel braking?” or, in the case of Diane Schuler’s accident, “Who is responsible?”. 

Several fundamental ideas that are frequently encountered in the field of investigation and traffic collision reconstruction are presented in this article. The following information provides an overview of these key concepts.

History of Traffic Collision Reconstruction

It was in 1985 that the National Highway Traffic Safety Administration provided funding for the initial development of a set of national guidelines to assist in the standardization of traffic collision reconstruction training. 

Because of this, a body known as the “Accreditation Commission for Traffic Accident Reconstruction” (ACTAR) was eventually established as an umbrella organization in the industry. 

Hugh H. Hurt Jr., the first to carefully study motorcycle accidents, is widely regarded as the father of this branch of vehicle collision research. 

His long and arduous reconstructions of motorcycle accidents led him to the following conclusions.

  • Wearing helmets effectively reduced the risk of head injuries.
  • Most motorcyclists needed additional driver training to better control skids.
  • A significant number of motorcycle accidents were caused by cars turning left in front of oncoming motorcycles.

What Is Traffic Collision Reconstruction?

According to field experts, accident reconstruction is a “branch of causation forensics that involves identifying the causes and consequences of accidents – accomplished first by accurately reading and analyzing the physical evidence left behind by accident before, during, and after the accident.” 

Accident reconstructionists essentially work backward, recording and examining the scene’s facts to conclude the accident’s cause and outcome. Road accident reconstruction experts in Canada could identify several factors that contributed to the accident, including:

  • Driving too fast
  • Running stop signs and red lights
  • Failure to make proper turns and lane changes
  • Failure of a car part or defect in a vehicle causes the driver to lose control of the vehicle
  • Road conditions that may have posed dangers to the driver

When Will a Traffic Collision Reconstructionist Be Part of My Case?

Reconstruction experts’ car accident reports, testimonies, and animation models are beneficial in settling disputes over an accident’s causes. As a result, in accident situations involving complex or controversial liability issues, attorneys frequently consult accident reconstructionists.

A traffic collision reconstruction expert may be able to assist you with your claim in the following ways:

  • A determination of the specific errors made by the at-fault driver that caused the accident (thus establishing liability)
  • Identifying the defective part or motor vehicle that contributed to the crash (which may entitle you to compensation through a product liability claim)
  • Poor road design and negligent maintenance of roads may be responsible for accidents caused by dangerous road conditions

Suppose the defendant(s) in the lawsuit assert that you contributed to the collision. In that case, Roar Engineering Accident Reconstruction Service may be able to assist you in defending your right to damages. 

In addition, our expert accident reconstruction team can help you prove your case against other drivers and parties who may also be accountable, increasing your chances of getting the total recovery damage.

How Is the Accident Reconstructed?

Personal injury lawyers must first accurately understand the clues provided by the physical evidence of the collision, then reconstruct and examine the events before, during, and after the accident to figure out how and why it occurred. Let’s find out how they do it. 


The investigation stage of accident reconstruction involves several steps. Specialists use the following essential elements to accurately interpret a collision scene.

  • Visiting the accident scene and examining all vehicles involved in the collision
  • Reviewing all victim, eyewitness, and police reports.
  • Examining physical evidence such as gauge and tire marks. (Tire marks provide information about whether the drivers involved in the collision reacted to danger or were unaware of the impending crash)
  • Examining the environmental conditions when the accident occurred

Suppose flames or explosions break out during a collision. Fire and explosion reconstruction experts can determine the cause of such collisions (Fire and explosions are among Roar Engineering’s many specialties).

Analysis of Data

The amount and nature of data provided determine which method or procedures are used to analyze a collision. For example, A momentum analysis can be used if there is enough physical evidence at the scene of the accident, such as skid marks before the impact, the point of impact, and where the vehicles stopped. 

Methods of assessing damage energy may be feasible if the accident vehicles are available for inspection. If the collision vehicles are not present, photogrammetry can be helpful. Using computer-based reconstruction or simulation programs can refine and improve manual calculation methods. 

3-dimensional laser scanning is becoming a common technique for documentation as well. A 3D point cloud can take measurements and build computer models for accident study. It’s a great way to trust the analysis and the conclusions if two or more methodologies get the same result.

We will discuss the analysis methods in more detail below.

Speed Calculation

Experts can use the length of a skid mark to determine, for instance, a vehicle’s initial speed. Because a driver often underestimates the speed of a car, an independent estimate of speed is crucial in accidents.

Additionally, inspecting the road’s surface is essential, particularly when traction has been lost because of black ice, diesel fuel pollution, or obstructions like road debris.

The car’s speed just before the collision is one example of the kind of helpful information that experts can obtain from an event data recorder.

3D Simulation and Forensic Animation

Experts can incorporate the 3D data into many computer simulation programs in accident reconstruction.

The 3D point clouds and models can also be used to create visuals to illustrate the analysis and show the involved drivers’ and witnesses’ perspectives.

Many new vehicles are equipped with “Crash Data Recorders or Event Data Recorders” (CDR or EDR). In addition, the Bosch CDR Tool is commercially available, offering a detailed analysis of crash data recorded directly from all supported vehicles.

Some parameters include pre-crash data, vehicle speed, brake status, throttle position, ignition cycles, delta-V, seat belt status, and others.


Photogrammetry is a method for determining physical evidence’s relative size and placement at a crash scene using images. Collision experts can use this method when reconstructionists cannot inspect the damaged vehicle, and collision experts can quantify property damage with reasonable accuracy.

High-quality photos are crucial. Multiple views of the item from various perspectives are necessary to enable the photogrammetry program to establish user-defined reference points. Naturally, the analysis is more accurate when more pictures and reference points are available.

Momentum Rule

Vehicle crashes are subject to the Law of Conservation of Momentum. This is because the two colliding automobiles make up the system in a two-vehicle collision. According to the Law, the system’s momentum before and after the crash must be conserved, meaning that the pre-impact and post-impact momentum must be equal.

Finding the cars’ pre-impact speeds is the primary goal of using momentum. To start the analysis, we need the mass of each vehicle, the direction before and after impact, and the vehicle’s post-impact speeds. 

By examining the physical evidence found on the site, such as intersection or road geometry, tire marks, or debris scatter patterns, it is possible to determine the directions of the cars both before and after the crash. In addition, it is possible to calculate post-impact velocities using the general velocity equation and the proper deceleration.


After the investigation is complete, forensic engineers put together diagrams, animations, and report results to create their expert testimony and collision-related conclusions. 

Forensic animation often shows the collision sequence in its entirety or a part of it as a video. It makes it easier for non-technical individuals, such as juries, to understand forensic findings about a collision sequence.

Animations need to be made by a person knowledgeable about physics, dynamics, and engineering to be physically realistic. Experts should carefully examine animations before being presented in a courtroom. 

It’s simple to abuse animation software since it enables one to portray motions that are not conceivable in the real world. The primary purpose of animation should be to visually represent the underlying calculations produced by the expert assessing the case. 

Reliable animations must be founded on physical data and analyses that adhere to the rules of physics.

Law Enforcement/Police Agencies

Forensic Collision Reconstructionists and Analysts are employed full-time by the Royal Canadian Mounted Police. The acronym ICARS (Integrated Collision Analysis and Reconstruction Service) is used in British Columbia to refer to them. There is an ICARS unit in every district of the Royal Canadian Mounted Police in the province.

The California Highway Patrol also uses the MAIT deployment (Multidisciplinary Accident Investigation Team). A team of investigators with advanced training in vehicle dynamics and collision reconstruction is formed for each squad. 

The members of the MAIT include a Motor Carrier Specialist I (MCS I), a Senior Transportation Engineer from Caltrans, two or more CHP officers, and a CHP Sergeant who acts as the team’s leader.


Cars, vans, trucks, motorcycles, and pedestrians can all be involved in a traffic collision reconstruction analysis. Numerous engineering principles are at the reconstructionist’s disposal for collision reconstruction. 

The same collision can be studied using one or more methods. A close agreement between the outcomes of two or more procedures increases confidence. You can get compensation for your case with the help of accident reconstruction tools, which allow you to explain your side of events clearly and efficiently in negotiations and court. 

No matter what type of vehicle is involved—a car, motorcycle, truck, or bicycle—we will work with you to find the facts about what happened and hold those accountable. Get in touch with our accident reconstruction team to get started.


What Is the Goal of Accident Reconstruction?

The study of the circumstances that cause collisions is known as accident reconstruction. Accident reconstructionists are employed by public sector organizations and private sector businesses to help determine what caused specific incidents.

What Do The 3 Stages of a Collision Include?

Three stages of collision can occur in a motor vehicle accident: vehicle, human, and internal collisions.

What Is the Difference Between a Collision and an Accident?

In contrast to collision, which implies that no one is to blame, an accident suggests that someone is.

Which Collision Type Is Considered to Be the Most Serious?

Head-on collisions are the most dangerous since they cause the most fatalities due to the tremendous force created during these incidents. A head-on accident is akin to running into a brick wall.