Legal & Dispute Support
Independent
Expert Witness
Independent technical reports for mechanical and electrical vehicle disputes, prepared by Jeremy Vinnicombe at Autodiag. Choose a document-only assessment of the available evidence, or enquire about a formal expert report for court proceedings under CPR Part 35.
Two report options
Most people choose the document-only route. The right report depends on the technical questions, the available evidence and how you need to use it.
Document-only
technical report
From £1,600 + VAT
An independent assessment of inspection reports, diagnostic records, repair history, photographs and relevant correspondence.
- Explains what the evidence supports and what remains uncertain.
- Identifies whether further investigation is needed.
- Helps you understand the technical issues in a vehicle or finance dispute.
Does not include a physical vehicle inspection or a formal CPR Part 35 report. The fee is confirmed against the agreed scope.
Enquire about a document-only report
CPR Part 35
expert report
From £4,900 + VAT
A formal, independent expert report for court proceedings, within the agreed instructions and Jeremy’s mechanical and electrical expertise.
- Sets out the evidence considered, technical opinion and limitations.
- Includes the required declarations and statement of truth.
- Considers the court’s directions, including single joint expert instructions where applicable.
Scope, fee and timetable are agreed in writing. Any inspection, additional work or court attendance is addressed in the quotation.
Enquire about a CPR Part 35 report
If a formal report is needed after a document-only assessment, we review the instructions and provide a written quotation for the work required.
Qualifications & Standing
Who I Am
Jeremy Vinnicombe, proprietor and principal diagnostic technician at Autodiag in Rugby. 28 years of hands-on automotive mechanical and electrical diagnosis and repair experience across independent workshop, fleet and specialist environments. Each expert instruction is checked against the technical questions and available evidence.
My core expertise is mechanical and electrical vehicle diagnosis and technical causation. Reports explain their evidential basis and limitations. For court work, my overriding duty is to the court, not to the person paying for the report.
Independent & Impartial
Opinions follow the evidence, including material that challenges the account given. The available information may support a point, contradict it or leave a question unresolved. Scope and conflicts are checked before accepting an instruction.
Formal Expert Reports
Where a CPR Part 35 report is instructed, it includes the relevant instructions, evidence considered, technical opinion, limitations and required declarations. Use in court is subject to the court’s permission and directions.
Areas of Expertise
Scope of Work
We assess mechanical and electrical vehicle issues using the relevant records and technical evidence. The need for a physical inspection is agreed case by case. Bodywork-only, paint and cosmetic assessments are outside this service.
Engine Failure
Timing chains, compression loss, bearing failure and lubrication problems. Assessment of possible causes, timing and evidential limitations using the vehicle records and relevant manufacturer information.
Turbocharger Failure
Underboost, overboost, oil-feed restrictions and bearing failure. Assessment of the possible failure mechanisms against the available diagnostic and inspection evidence.
Electrical & Electronic
ECU, wiring, sensor and CAN-network faults. Interpretation of diagnostic records alongside the system behaviour and relevant test results.
Transmission
Gearbox, clutch, differential, DSG and automatic transmission faults. Technical assessment against the service history, mileage and reported sequence of events.
Known Manufacturer Defects
Relevant technical service bulletins and documented model-specific failure patterns, checked for applicability to the vehicle. A known issue alone does not establish the cause in an individual case.
Used Vehicle Disputes
Independent technical evidence for used-vehicle quality disputes, finance complaints and Financial Ombudsman Service cases. Legal liability and entitlement are matters for the parties, their advisers and the decision-maker.
How It Works
The Process
We agree the scope, fee and timetable before work starts. Tell us about any court order or deadline when you first enquire.
1
Outline the Case
Email a brief outline, vehicle details, parties and any deadline. We check scope and conflicts before requesting the evidence.
2
Agree the Instruction
We confirm the report type, technical questions, evidence required and written quotation. Joint instructions follow the court’s directions.
3
Assess the Evidence
The records and relevant technical information are assessed. Any gaps, competing explanations or need for inspection are identified.
4
Issue the Report
You receive the agreed written report, with its findings and limitations. Formal CPR Part 35 reports include the required declarations and statement of truth.
Before you enquire
Which report should I choose?
A document-only report can help you understand the technical evidence in a dispute. If a court has directed expert evidence, or a formal CPR Part 35 report may be needed, tell us before commissioning work so we can confirm the appropriate scope.
Is a CPR Part 35 report always based on an inspection?
No. The appropriate evidence and any need for an inspection depend on the questions being asked. We agree the scope before accepting the instruction and state limitations in the report.
Can I move to CPR Part 35 later?
If a formal report is needed later, we review the instructions and evidence and provide a written quotation for the work required. Discuss any court deadline before commissioning the initial report.
Will the report support my claim?
Our opinion follows the evidence. It may support some points, challenge others or identify questions the available information cannot answer. For court work, the expert’s overriding duty is to the court.
Can I recover the cost of the report?
Recovery of fees depends on the process, any applicable rules and the decision or agreement in your case. It is not guaranteed. Your legal adviser can advise on recovery and court permission.
Start Your Enquiry
Email a brief outline, the vehicle details, names of the parties and any relevant deadline. Tell us about any court directions or proposed single joint instruction. We will check scope and conflicts before requesting the evidence needed.
Autodiag provides independent technical opinion, not legal advice. Reports explain the evidence considered and any limits on the opinion. Opinions may change if further evidence emerges. Use of expert evidence in court is subject to permission and directions. Jeremy Vinnicombe trades as Autodiag, VAT registration GB286590361.