The role of expert witnesses in motorcycle crash cases

Safe System Solutions offers transport and road safety expert witness services and litigation support across Australia, including specialist expertise in motorcycle crash cases. 

The role of an expert witness is to help the court understand the complex factors involved in these types of crashes, including: 

Accident Reconstruction (Crash Reconstruction) 

One of the primary roles of an expert witness in a motorcycle crash case is crash reconstruction. These experts use scientific and engineering principles to analyse how a crash occurred. In motorcycle crashes, this can involve: 

• Analysing the scene: Experts examine the crash site to gather physical evidence, such as skid marks, debris, tire impressions, and vehicle damage. In the case of a motorcycle crash, they may also assess the condition of the motorcycle itself. 
• Reconstructing the events: Using their knowledge of vehicle dynamics, physics, and human behaviour, crash reconstruction model how the crash unfolded. For example, they can calculate the speed of the motorcycle at the time of the crash, the trajectory of the rider, and the forces involved in the collision. 
• Identifying factors: Experts help determine what contributed to the crash. Was the motorcyclist speeding? Was the road surface slippery or poorly maintained? Did the motorcyclist fail to see a hazard or misjudge the distance to another vehicle? 

Analysis of Motorcycle-Specific Dynamics 

Motorcycle crashes have unique dynamics compared to car crashes, so experts who understand motorcycle behaviour are essential: 

• Handling characteristics: Motorcycles behave differently from cars, turning them requires different input, front- and rear-brake operation is usually independent, and weight transfer during braking is more pronounced. An expert can assess how the rider’s input and the motorcycle’s handling characteristics may have played a role. 
• Braking and stopping distances: An expert can calculate whether the motorcyclist had enough time to stop before hitting an obstacle or another vehicle. Motorcycles require different stopping distances than cars, depending on the condition of the road, the tires, and the bike’s braking system (e.g., anti-lock brakes). Motorcycles also have different braking characteristics than cars, especially in corners. 
• Vulnerability of the rider: Motorcyclists are more vulnerable in crashes because they are exposed and lack the protective structure of a car. Experts can explain how this increased vulnerability may have influenced the severity of injuries.  

Road Safety and Infrastructure 

Experts in road safety assess whether the road design or condition contributed to the crash, which is particularly relevant in motorcycle crashes due to the bike’s vulnerability on certain types of road surfaces. They consider: 

• Road design and maintenance: The expert evaluates whether the road was properly designed and maintained for motorcyclists. For example, poorly marked curves, potholes, gravel on the road, or improper signage could contribute to motorcycle crashes. 
• Visibility issues: Road experts can assess whether the motorcyclist had adequate visibility at the time of the crash. For instance, they might analyse whether the road had poor lighting, obstructions, or blind spots that made it difficult for the motorcyclist to see approaching traffic or hazards. 
• Safety features: Experts may examine whether safety features, such as guardrails, barriers, and bike lanes, were present and whether they could have prevented or mitigated the crash. Some roads may not be designed with motorcyclists in mind, and an expert might highlight whether road safety standards were met. 

Biomechanics and Injury Causation 

In personal injury claims resulting from motorcycle crashes, biomechanical experts are often called to analyse how the forces in the crash impacted the rider’s body. These experts can help explain: 

• Injury mechanisms: The biomechanical expert assesses how the forces of the crash caused specific injuries to the rider. For instance, they analyse the rider’s position during the crash, the impact, and how the injuries may have been caused by contact with the road or the motorcycle. 
• Protective gear: They may also evaluate whether the rider was wearing appropriate protective gear, such as a helmet, gloves, or leathers, and how these items affected the severity of injuries. They can explain the effectiveness of these safety measures in reducing injury severity. 
• Causation of injury: The expert can determine whether the injuries were likely caused by the motorcycle crash itself, as opposed to other factors, and can also evaluate long-term consequences of the injuries. 

Behavioural factors 

Experts in human factors and behavioural science assess the contribution of human error and other behavioural factors to a crash.  

This is a specialist area of expertise that interacts with other factors such as road safety and infrastructure and injury causation. Rider behaviour contributes significantly to motorcycle crashes and the crash outcome, and an expert in this field can help to assess the underlying reasons for that behaviour. 

 This can include aspects such as: 

• Human error relating to attentiveness, drowsiness/alertness, judgement, visibility, and travel speed. 
• Illegal behaviour or risk-taking relating to alcohol or other drug use, speeding, unlicenced riding, red-light running, and distraction. 
• Consideration of wider contextual factors in the system that may have influenced those illegal or high-risk behaviours.     

 Motorcycle Safety and Standards 

Experts in motorcycle safety may be involved in cases where product defects or failures are suspected. For example, if a defect in the motorcycle’s design or manufacturing contributed to the crash, a safety expert could analyse: 

• Defective parts: Experts may look into whether faulty parts, such as brakes, tires, or suspension systems, contributed to the crash. 
• Motorcycle design issues: In some cases, an expert might assess whether the design of the motorcycle was inherently unsafe, especially if it did not comply with industry safety standards or had a history of mechanical issues. 
• Standards and regulations: They may also evaluate whether the motorcycle or its components were manufactured in accordance with safety regulations and standards, and if any lapses contributed to the crash. 

Testimony and Expert Reports 

Expert witnesses in motorcycle crash cases typically provide written reports and testimony in court. The report details their findings, analysis, and conclusions. For example, an expert might explain how a specific road defect, rider behaviour, or motorcycle malfunction caused the crash. 

• Written report: The expert’s report includes the methods used to analyse the crash (e.g., crash reconstruction software, vehicle data analysis) and provides an objective opinion on the likely cause of the crash. 
• Court testimony: In court, the expert may be asked to explain their report in simple terms for the judge or jury. They may also be cross-examined by the opposing side, requiring them to defend their findings and methodologies. 

Expert witnesses in motorcycle crash cases help the court understand complex technical and scientific principles, enabling it to make an informed decision regarding liability, damages, and road safety improvements. 

Safe System Solutions offers our expert witness services and litigation support in the following areas: