Vehicle Accident Investigation and Root Cause Analysis Template

What is a vehicle accident investigation?

An accident report records what happened on the day: the place, the time, the parties and the damage. An investigation comes after it and answers a different question: why did the accident happen, and what has to change so it does not happen again. So an investigation collects more evidence, puts it in a timeline, then looks for the root cause and sets actions with an owner and a date.

This vehicle accident investigation template starts where the Vehicle Accident Report Form ends. Its aim is to prevent a repeat, not to find someone to blame. If the investigation ends at "driver error" and nothing else, it is not finished.

Which tracking and camera data do you review before the accident?

If the vehicle has a tracking device or a camera, you have a record of what happened before the accident that does not depend on memory. The form asks for these items, each with its source:

• Speed at impact and the speed limit at the location. Take the limit from signs or the map; it may be a temporary limit in a roadworks zone.
• Highest speed in the last 10 minutes, and harsh driving events in the last 30 minutes: braking, acceleration and sharp cornering.
• Continuous driving before the accident and the time of the last rest, plus the trip start and the distance to the accident.
• Whether the vehicle was on the planned route, and the seat belt if the vehicle has a sensor for it.
• The video clip and gaps in the data, such as signal loss or a device that stopped.

Export this data on the day of the accident. Some devices overwrite old recordings after a set time, so find out what that time is on yours. The Fleet Camera Storage & Data Calculator estimates the capacity you need to keep clips for longer.

How do you investigate a vehicle accident, step by step?

1. Save the data first. Export the route, speed and events for the whole trip, and save camera clips and photos somewhere permanent.
2. Set up the investigation team. A lead who was not involved in the accident, plus someone who knows the daily work, such as a dispatch or workshop supervisor.
3. Collect the evidence and record where it is kept. Driver and witness statements, the authority report, the daily check, the maintenance record and the trip schedule.
4. Build the timeline. One line for each key moment with its source, and a mark when two sources agree on it.
5. Analyze the causes. Go through the seven categories, then apply the 5 whys until you reach a cause you can fix.
6. Set the actions and follow them up in the Excel register until they are done, then check that they worked after a period you choose.

Which cause categories does the accident root cause analysis use?

The form asks about each category: did it contribute to the accident? More than one category can contribute to the same accident. The same categories are in the drop-down on the register, so the summary counts them:

How do you find the root cause of an accident with the 5 whys?

Start with the event and ask "why?" about each answer until you reach a cause an action can fix. Five is a rule of thumb. An example from investigation RCA-0002 in the register:

1. Why did the truck hit the stopped vehicle? The driver braked late at 92 km/h in a 60 km/h zone.
2. Why did he brake late? He did not notice the roadworks signs before the zone.
3. Why did he not notice them? He was reading a phone message that changed the next delivery address.
4. Why did the message reach him while driving? The dispatch procedure allows route changes to be sent to drivers at any time.

The root cause is a work procedure that allows messaging a driver who is driving; its category is Procedures and training. The trip running 40 minutes behind schedule is a contributing cause. Had the investigation stopped at the first why, it would have ended at "speed", and the procedure behind it would have stayed as it was.

How do you choose corrective and preventive actions?

Start with the strongest action, and move to a weaker one only if the stronger one is not possible:

1. Remove the hazard: stop a trip, route or practice until the cause is dealt with.
2. Vehicle or site change: a repair, a phone holder and hands-free kit, or a marked pedestrian walkway.
3. Written work procedure: a clear rule, such as no route changes while the vehicle is moving.
4. Training and awareness: a pre-shift toolbox talk or practical training.
5. Monitoring and follow-up: a regular review of specific alerts to show the change has held.

Each action has an owner and a due date. After it is done, check that it worked: for example, review speed alerts on the same route a month later. If nothing has changed, the analysis needs another look.

How does the Excel register calculate investigation and action status?

The as-of date is today unless you type a fixed date on the Lists sheet. The investigation deadline there is 14 days and the due-soon warning is 7 days; both are example values to change to match your company procedure. An investigation row shows a check message when the video clip was not saved, when the investigation ended with no root cause or no actions, or when one of its actions has no owner.

Worked example: a collision in a roadworks zone

On 8 September 2026 a truck hit the rear of a stopped vehicle on the highway before exit 18, and the other driver had a minor injury. These are the example figures in the register:

• Speed at impact 92 km/h, temporary limit 60 km/h: over limit = 92 − 60 = 32 km/h. Tracking logged 3 harsh driving events in the last 30 minutes and 4.3 hours of continuous driving.
• The investigation started on 9 September and ended on 19 September: days to investigate = 10 days, inside the 14-day example deadline.
• The investigation has 4 actions. On 15 October two are not done, so its status is Complete, actions open.
• With an as-of date of 15 October 2026 (the file uses today's date): the phone holder action was due on 10 October and is not done: its status is Overdue, with 15 − 10 = 5 days late. The weekly review action is due on 20 October, 5 days away, which is less than 7, so its status is Due soon.

Common vehicle accident investigation mistakes

• Saving the data too late. A camera clip can be overwritten before anyone asks for it, as in investigation RCA-0003 in the register.
• Stopping at "driver error". Ask why the error happened: a tight schedule, a missing procedure, or a vehicle unsuited to the route.
• Relying on one source. The driver's account alone, or the tracking data alone, is not enough. Compare at least two sources for each key moment.
• Actions that only "remind drivers". A reminder is the weakest action. Look first for a change to the vehicle, the site or the procedure.
• Closing the investigation before the actions are done. That is why the register keeps its status at "Complete, actions open" until the last action is done.
• Ignoring earlier reports. Search the near-miss log for reports at the same place or in the same category; they may have warned of the hazard before the accident.

What the template does not do

The template is an internal tool to prevent repeats. It does not decide legal liability for the accident, and it does not replace the authority report or the insurer's process. Tracking data is approximate: GPS accuracy and the device reporting interval affect the recorded speed and time, so read it alongside the other sources. Report accidents and injuries under your authority's current requirement, estimate the cost in the Road Accident Cost Calculator, and record it in the Fleet Incident and Claims Log.