Assessment Insights

Vehicle assessment involves more than identifying damage and calculating repair costs.

An assessor may need to consider the circumstances of an incident, physical evidence, repair methodology, vehicle condition, market information, technical data and the documentation available at the time.

Assessment Insights provides practical information about the reasoning, evidence and professional judgement that can sit behind an assessment decision.

Why Evidence Matters

An assessment opinion should be supported by the evidence available.

That evidence may include physical damage, photographs, repair estimates, invoices, diagnostic information, vehicle history, manufacturer information, market data and accounts of how an incident occurred.

Not every piece of information will carry the same weight. Part of the assessment process is determining what is relevant, what can be verified and whether the available evidence supports the conclusion being reached.

New information can also change an assessment. Additional damage may become visible during dismantling, further documents may become available, or technical information may clarify an issue that could not initially be determined.

Changing an assessment when reliable new evidence becomes available is not necessarily an inconsistency — it can be part of a sound assessment process.

Evidence, Opinion & Assumption

A useful assessment separates what can be established from the evidence from what is opinion, interpretation or assumption.

Evidence may establish observable facts — the condition of a component, the location and characteristics of damage, a documented repair operation, diagnostic information or an established market transaction.

Professional opinion involves interpreting that evidence using relevant experience, technical information and an appropriate assessment methodology.

Assumption becomes problematic when something that has not been established is treated as fact, particularly where that assumption materially influences the assessment outcome.

Where information is incomplete or an issue cannot reasonably be determined, that limitation should be recognised rather than filled with an unsupported conclusion.

A well-supported assessment should allow another person to understand not only the conclusion reached, but the evidence and reasoning that led to it.

When Assessments Differ

Two assessments of the same vehicle or matter do not always produce identical conclusions.

Differences can arise because assessors have been provided with different information, inspected the vehicle at different stages, applied different repair methodologies or relied upon different technical or market evidence.

Relevant differences may include:

  • the information and evidence available to each assessor

  • whether the vehicle was physically inspected or reviewed remotely

  • the stage of dismantling when the assessment occurred

  • repair versus replacement methodology

  • interpretation of manufacturer repair information

  • labour, parts and specialist operations included in the repair scope

  • vehicle condition and pre-existing damage

  • valuation methodology and comparable vehicles used

  • new information becoming available after an earlier assessment.

A difference of opinion does not, by itself, establish that either assessment is unreasonable.

The important question is whether the conclusion can be supported by the evidence, methodology and reasoning used to reach it.

Causation & Pre-Existing Condition

Not every defect or item identified during an assessment will necessarily have resulted from the incident being considered.

A vehicle may already have wear, deterioration, previous damage, earlier repairs, corrosion or mechanical conditions that existed before an incident occurred. Equally, incident-related damage can sometimes expose or worsen an existing condition.

An assessment may therefore need to consider:

  • the location and characteristics of the damage

  • whether the damage pattern is consistent with the reported incident

  • vehicle age, use and general condition

  • evidence of previous damage or repair

  • wear, deterioration and corrosion

  • service, maintenance or repair history where relevant

  • photographs or other evidence showing the vehicle's earlier condition

  • whether an incident caused, contributed to or simply revealed an existing issue.

Where causation cannot reasonably be established from the available evidence, that limitation should be identified.

The presence of a defect after an incident does not, by itself, establish that the incident caused it. Equally, an existing condition does not automatically mean subsequent damage is unrelated.

The Importance of Documentation

Good documentation helps establish what was known, observed and decided at different stages of a matter.

Photographs, estimates, invoices, assessment reports, diagnostic information and correspondence can provide a contemporaneous record that may become particularly important if questions arise later.

Useful documentation may include:

  • photographs showing damage and vehicle condition

  • initial and supplementary repair estimates

  • assessment reports and repair authorities

  • parts quotations and availability information

  • invoices and records of completed work

  • diagnostic scans and calibration records

  • manufacturer repair information where relevant

  • valuation evidence and comparable vehicles

  • dated correspondence between the parties

  • records of significant decisions or changes to the repair scope.

Documentation should also be considered in context. A photograph may establish physical condition but not necessarily causation; an estimate records proposed work but does not establish that the work was completed; and an invoice records a charge but may not, by itself, establish the technical necessity of that operation.

Strong documentation creates a traceable record of the evidence and decisions behind an assessment.

Assessment at a Point in Time

An assessment reflects the information and evidence reasonably available at the time it is undertaken.

During the course of a matter, circumstances can change. A vehicle may be dismantled, additional damage discovered, further technical information obtained, parts availability confirmed or new documentation provided.

As a result, an earlier assessment may need to be reviewed or amended.

When considering an earlier assessment, relevant questions can include:

  • what information was available at the time

  • what could reasonably be observed or verified

  • whether the vehicle had been dismantled

  • whether relevant technical information was available

  • what assumptions or limitations were identified

  • what new evidence subsequently became available

  • whether that new information reasonably changes the earlier conclusion.

An assessment should be considered against the evidence available when it was made, while remaining open to revision when reliable new evidence becomes available.

Supplementary Assessments

A repair estimate and initial assessment are often prepared before a vehicle has been fully dismantled. As repairs progress, additional damage, parts or repair operations may be identified that were not reasonably apparent during the initial assessment.

A repairer may then submit a supplementary estimate or supplementary assessment request, commonly referred to as a supplement, for consideration.

A supplement may arise because of:

  • concealed damage identified during dismantling

  • additional components found to require repair or replacement

  • changes in parts prices or availability

  • additional labour or repair operations

  • manufacturer repair procedures identified during the repair

  • mechanical, electrical or diagnostic requirements

  • ADAS scanning, programming or calibration

  • sublet or specialist operations

  • changes to the repair method as further evidence becomes available.

What happens to the additional cost?

The submission of a supplement does not necessarily mean the additional amount will automatically be authorised.

The insurer or assessor may review whether the additional work is related to the incident, whether it is technically necessary, whether the proposed repair method is appropriate and whether the labour, parts and other charges are reasonable.

The repairer and assessor may therefore need to exchange photographs, measurements, technical information, quotations or other evidence before the revised repair scope is agreed.

A supplement is an important part of the assessment process because it allows the repair scope and cost to respond to information discovered after the original assessment.

Supplementary assessment can also affect repair timeframes. Where additional work requires approval, further parts or specialist services, the vehicle may remain unavailable while the revised repair scope is resolved.

Current Publications

Explore completed articles examining evidence, assessment practice and professional judgement.

Need More Clarity?

If an assessment decision, repair scope, valuation or technical conclusion is unclear, an independent review can help identify the evidence relied upon and the reasoning behind the position reached.

The purpose of an independent assessment is not simply to produce a different opinion. It is to examine the available evidence and determine whether the technical position can be reasonably supported.