Useful documentation: report, photos, sketches and witnesses

The quality of the expert report depends largely on the quality of the available documentation. The sooner the information is collected, the better the subsequent reconstruction will be. This article explains the elements that add the most value to a technical analysis.

Attestation and official documentation

The police report is the starting point in most traffic accidents. It must be requested in full, with:

• Complete procedures and annexes.
• Official signed sketch and to scale, when it exists.
• Photographs of the report.
• Statements from all parties.
• Technical data of the vehicles.

In work or domestic accidents, the equivalent are Labor Inspection reports, formal complaints or communication reports to the person in charge of the space.

Photographs

Photographs are one of the most useful pieces of evidence, as long as they are taken well. It is recommended:

• Capture the accident site from various angles.
• Include scale references, such as a coin or ruler.
• Photograph damage to vehicles, elements or furniture.
• Document signage, lighting and state of the environment.
• Save the original metadata (date, time, location).

An isolated image is rarely enough. The addition of images from different perspectives allows the scene to be reconstructed.

Sketch and measurements

A useful sketch should include:

• Distances between relevant elements.
• Final positions of the vehicles or the injured party.
• Visible braking, drag or fingerprint marks.
• Environment elements: signs, traffic lights, obstacles.
• Orientation (north) and direction of circulation.

When there is no official sketch, the expert can make his own from measurements on the ground, if the scene is still accessible.

Witnesses

Witness statements are useful but must be used judiciously. A good witness provides:

• Specific data: position from which you observed, distance, moment.
• Sequential, non-interpretive description.
• Contact details available.

The testimonies are contrasted with physical evidence. When they coincide, they reinforce the reconstruction; When not, the reasons are analyzed.

Technical data

• Make, model, year and registration of the vehicle.
• ITV status.
• Insurance and policy details.
• Recent maintenance history, if relevant.
• Records of the vehicle itself (dashcam, GPS, telemetry).

Medical reports

When the accident has caused injuries:

• Initial emergency medical report.
• Monitoring reports.
• Medical discharge and sequelae, if they exist.
• Complementary tests (x-rays, MRIs).

These documents are essential if a biomechanical compatibility study is carried out.

Common errors

• Remove the vehicle or clean the place before documenting.
• Repair without leaving a record of the previous state.
• Photographs out of focus or without references.
• Losing contact with identified witnesses.
• Not requesting the report on time.

Next steps

• Please refer to the full process.
• Review the reconstruction specialty.
• Contact from contact or the help center.