Vehicle Examinations
Vehicle Examinations
Vehicle Examinations

Highlighted terminology is explained at the bottom of the page.


As all collisions involve a vehicle, it is vitally important that they are examined for evidence to determine the collision and injury mechanism, as well as any contributory or causative factors. As an evidential item, the collision-involved vehicles should be one of the first investigative opportunities undertaken to identify, secure and record the evidence they hold.

Even when the vehicle has been previously examined, our strong advice is that we further examine the vehicle to ensure nothing has been missed. Furthermore, in order to perform an objective analysis and produce a robust reconstruction of a collision, all forensic collision investigators should be offered the opportunity to investigate all three main collision factors; the collision-involved vehicle, the collision environment and the actions of the road users.

Our vehicle examinations consist of two fundamental aspects:

Vehicle Evidence Examination – The careful examination and scrutiny of any evidence contained on or within a collision-involved vehicle.

Vehicle Roadworthiness Examination – The careful examination and scrutiny of the automotive components and systems of a collision-involved vehicle.

Where required, although not limited to, we perform the following further investigative vehicle-related activities:

Vehicle Forensics – A specialised service involving the extraction of vehicle-borne data from infotainment devices. Please click here for this service.

Crash Data Recorder – A specialised service involving the extraction of vehicle-borne crash data from Restraint Control Modules (also referred to as the Airbag Control Module, Sensing Diagnostic Module and collectively as Event Data Recorders). Please click here for this service.

Vehicle Headlamp Beam Profiling - The forensic mapping of a vehicle's headlamp beam.

Vehicle Blindspot Identification and Profiling - The forensic mapping of a vehicle's horizontal and vertical blindspots.

Vehicle Mirror Coverage Profiling - The forensic mapping of a vehicle's mirror coverage.



Vehicle Evidence examination


Both the inside and outside of a vehicle contain a wealth of information that requires a detailed examination to identify all the crucial evidence. Unless a vehicle has been thoroughly examined, there is the potential for vital witness marks to be missed. Some of the aspects of a collision-involved vehicle we investigate are briefly introduced below.

Vehicle Contact Marks

Examination of the vehicle's exterior is crucial in collisions where a vehicle has collided with pedestrians, motorcyclists and pedal cyclists. The identification of vehicle contact cleaning marks and vehicle contact marks are vital when determining both the collision dynamics and injury mechanism. Typical contact marks are streaked hand prints on vehicle bonnets, cleaning marks on the leading elevations of the front bumper cover where pedestrian legs first contact the vehicle, and contact marks formed by handlebars from a pedal cycle to name only a few.

Vehicle contact marks give rise to the objective analysis of the impact configuration. This vital evidence leads onto the determination of respective approach paths, and from them, there is a much higher likelihood of the entire collision sequence being identified.

Vehicle Damage Profile

The recording of the vehicle damage profile allows for the determination of the principal direction of force which is a fundamental consideration in any computer simulations and forensic animations. The vehicle damage profile for pedestrian, motorcyclists and pedal cyclists collisions is the primary evidence used to determine the impact configuration and subsequent collision sequence objectively.

Injury Mechanism

Examination of the vehicle’s interior may provide evidence in relation to various aspects of the driver actions and vehicle factors. For example, we may determine the occupant dynamics during the collision, the status of any control switches and settings, the area of view for the driver and the available access to the control pedals. During collisions and other incidents, such as evasive steering or emergency braking, the occupants inside the vehicle (or riding on) may interact and engage in such a way as to cause injury. Occupant dynamics closely relates to the injury mechanism, however, where contact occurs between an occupant and the interior of a vehicle it is specifically referred to as the occupant contact area. Some of the indicators of occupant contact areas are hair, body fluid, bodily matter, cosmetics and fabric transfers. Imprints of vehicle occupant features may form on plastic trim components such as teeth marks or earring scrapes. Long hair can trap in window seals or between crushed vehicle panels. To some of our clients it is essential we investigate the occupant dynamics so that we can determine the mechanism of injury. However, it must be understood that we do not comment on injury.

Safety Restraints

There is a multitude of occupant safety systems fitted to modern vehicles. While we offer our clients the option to have both the primary vehicle safety and secondary vehicle safety systems checked, most common are the active restraints and passive restraints. Safety belts are an active restraint and are reliant on the vehicle occupant manually applying them. The use of safety belts by vehicle occupants is associated with the level of injury sustained. This injury can also assist in identifying the person who was seated in a particular seat due to the direction of associated body marks and injuries. We are experienced in examining safety belts for correct usage. High contact pressures during a collision may cause the plastic housing of both the latch plate and shoulder guide loop on the B or C-pillar to fuse with the webbing, and our inspection is nearly always conclusive. We examine both sides of the webbing for signs of loading. Excess point loading produces significant friction between the webbing and latch plate and/or webbing and shoulder guide loop at the B or C-pillar forming witness marks. Some webbing is designed to stretch during a collision, and older versions may have energy management loops, which are a series of threaded folds located near anchorage points that break away under high tensile loading. For our seat belt examination service, please click here.


Fundamental to a driver’s ability to safely travel their intended route is the available view they are provided with of the road ahead. Checking for any obvious defects or reduction to the level of visibility through the windscreen is paramount in all collisions and can never be overlooked. We look for dry wiping marks caused by the dry smearing of foreign debris through the swept area. Internal and external foreign debris, such as dust and road grime, can build up during storage post-recovery or may have formed from the presence of an air ambulance at the collision scene. This layer of foreign debris can produce significant disablement to a driver’s forward field of view in sunny conditions.

Often damage to windscreens is misinterpreted, and it is important we distinguish between contact and induced damage. The head, arm, shoulder, legs or any part of a pedestrian can strike the windscreen, as well as any objects or vehicle components from other collision-involved vehicles. At the same time, an object from within the vehicle may strike it due to its inertia or the inertia of an unrestrained occupant may cause them to move forward relative to the decelerating vehicle and strike the windscreen. The front passenger airbag may deploy and often strikes and cracks the nearside lower windscreen area; the driver’s airbag occasionally does the same, but due to it being housed in the steering wheel its standoff distance is greater and is less likely than the front passengers to strike the windscreen.

We can map any blind spots caused by the A and B pillars and any other such obstructions within the occupant compartment. Furthermore, we can map the mirror coverage.

Foot Control Pedals

The available access of a driver to the foot-operated vehicle control pedals is fundamental to their ability to control a vehicle. If a driver is unable to control the foot pedals or their level of application is reduced, then the risk of a collision increases. Any obstructions to the pedals in the footwell or any loose items within it or under the driver’s seat can give rise to an inability to apply sufficient braking pedal force. Water bottles are commonly found rolling about inside vehicles, and if they were to make it under the foot pedals, they might restrict the amount of pedal travel.

At times accelerator pedals may stick momentarily at wide open throttle (WOT) due to aftermarket floor mats mounted on top of the factory fitted ones; square pattern shapes of the uppermost mats may allow accelerator pedals to become temporarily held in the fully depressed position.

Control Switches

Identifying and recording the positions of various control switches offers valuable insight to driver behaviour and includes indicators, headlights, heating ventilation air conditioning (HVAC) and wipers/washers. For pedestrian collisions where the vehicle has been reversing, we ensure the reversing lights and any required audible warning devices operate correctly.

Instrument Cluster Readings

The instrument cluster may contain a wealth of information, from the speed of impact to the amount of fuel left. Depending on the collision-involved vehicle some or all of the instrument needles may return to their default resting position when the power is lost; others remain fixed, commonly referred to as frozen needles or residual readings. Not all instrument needles return to their default resting position when power is removed, with the most common being the fuel indicator. When power loss is sudden, such as that from an impact, then some instrument needles may remain stuck at their last value. The main consideration is whether there is an indication of speed. Some of the methods we use to assess the robustness of any indicated speeds is through the identification of needle slap witness marks and drivetrain/tyre sizes/tachometer mathematics. Residual readings on speedometers with low resistance to needle motion are not reliable indicators of a vehicle’s speed at impact, even with a sudden power loss coincident with the point of impact as the needles can be subject to external forces and move post-impact. Alternatively, residual readings on speedometers with high resistance to needle motion can represent that vehicle’s speedometer reading at the point of impact, again provided that there be a sudden power loss coincident with the impact.


Vehicle roadworthiness examination


A vehicle roadworthiness examination seeks to identify any defective automotive components, which may have been contributory or causative to a collision.

Our examinations thoroughly check the central safety critical components including the foot pedals, handbrake, steering, braking, tyres, obligatory lamps, mirrors and suspension components.

As standard, we perform electronic downloads to identify any Diagnostic Trouble Codes (DTCs), and where necessary we record live engine data and perform electronic system tests.

When there are allegations of automotive defects, we strip down and inspect all of the suspected component parts. In particular, we have experience in stripping down full braking systems, including the discs, pads, calipers, brake hoses, ABS modulator, master cylinder, servo, push rod and brake pedal.

Although we are guided by the matters of instruction, our vehicle roadworthiness examinations are both comprehensive and thorough.



Vehicle Examinations
Vehicle Examinations
Vehicle Examinations


Fees & Lead Times

Our service level agreements for fees and lead times for our vehicle examination services vary due to the complexity of each case and any additional investigative services required.

This service is part of our all inclusive investigative reconstruction package.

Please contact us to discuss your requirements.




Active Restraint - A restraint system that is reliant on the action of its user.

Approach Path – The geometric description of the course over ground of the collision-involved vehicles, objects or persons during the pre-collision phase.

Causative Factor - An event, circumstance or condition that causes a collision.

Collision Dynamics – The forces and motions occurring during a collision due to the interaction and engagement of collision-involved vehicles, objects or persons.

Collision Environment - The settings, surroundings and conditions concerning a collision site at the time of a collision.

Collision Factor – An event, circumstance or condition relating to a collision scenario.

Collision Sequence – The chronological sequence of events involving the collision-involved vehicles, objects or persons.

Collision-Involved Vehicle – A vehicle directly related to a collision.

Contact Mark - A mark created following an interaction with another item.

Contributory Factor - An event, circumstance or condition that contributes to a collision.

Impact Configuration – The position and heading of each collision-involved vehicle and pedestrian at the initial time of impact.

Injury Mechanism – The mechanical behaviour leading to an injury.

Occupant Dynamics - The forces and motions occurring to vehicle occupants due to their interaction and engagement with the collision-involved vehicle, and any objects or persons within.

Occupant Contact Area - An area of contact between a vehicle and its occupant.

Passive Restraint - A restraint system that does not rely on the action of its user.

Primary Vehicle Safety - Vehicle systems and features designated to reduce the occurrence of road vehicle collisions.

Principal Direction of Force (PDOF) – The direction of the vector along which the principal force is applied to the vehicle.

Road Users – Persons on the road including drivers, vehicle riders, pedestrians or passengers.

Safety Belt - An arrangement of straps with a securing buckle, adjusting devices and attachments which is capable of being anchored to the interior of a power-driven vehicle and is designed to diminish the risk of injury to its wearer, in the event of collision or of abrupt deceleration of the vehicle, by limiting the mobility of the wearer's body.

Secondary Vehicle Safety - Vehicle systems and features designated to reduce the injury consequences of a road vehicle collision.

Vehicle Contact Cleaning Mark - A mark created on a collision-involved vehicle following an interaction with another collision-involved vehicle, object or person which rubs or wipes clean some or all of the surface debris at the contact point.

Vehicle Contact Mark - A mark created on a collision-involved vehicle following an interaction with another collision-involved vehicle, object or person.

Vehicle Damage Profile - The arrangement of damage to a collision-involved vehicle.

Witness Mark - A mark providing contrast against its surrounding surface that serves as an indicator of interaction.


our Services

All Inclusive Service Collision Accident

All-Inclusive Investigation

Collision Reconstruction Collision Accident

Investigative Reconstructions
Desktop Analysis Collision Accident

Desktop Analysis
Claim Validation

Claim Validations
Vehicle Examinations Collision Accident

Vehicle Examinations
Laser Scanning Collision Accident

3D Laser Scanning
Forensic Animations Collision Accident

Forensic Animations
CCTV Digital Video Analysis Collision Accident

Digital Video Analysis
Collision Site Analysis Collision Accident

Collision Site Analysis
UAV Collision Accident

UAV Aerial Imagery
Collision Accident Computer Simulations

Computer Simulations
Collision Accident Vehicle Forensics Infortainment

Vehicle Forensics
Collision Accident Crash Data Analysis

Crash Data Analysis
Collision Accident Light Bulb Analysis

Lamp Analysis
Collision Accident Seat Belts

Seat Belt Examinations
Incident Analysis

Incident Analysis
Collision Accident Photography

Site Photography
Collision Accident Scale Plan

Scale Plans
Collision Accident Report Validation

Report Confirmations