How to Instruct a Contract Loss Expert Witness
Identify Loss Type
Lost profits? Wasted expenditure? Construction quantum? Professional negligence? Each determines which expert profile you need, forensic accountant, quantity surveyor, or economic damages specialist.
Identify Sector
Construction? Technology? Supply chain? Financial services? Sector expertise matters, industry comparables and sector economics are central to loss quantification.
Civil or Arbitration?
CPR Part 35 (civil courts) or LCIA/ICC/UNCITRAL rules (international arbitration)? Different procedural requirements apply to expert reports, disclosure, and joint expert meetings.
SJE or Party-Appointed?
Has the court directed a Single Joint Expert? Or will each party appoint their own expert? SJE instructions require joint letters; party-appointed experts require separate engagement.
Check Credentials
ACA/FCA for financial losses; MRICS/FRICS for construction quantum; sector experience verified; CPR Part 35 report history; professional indemnity insurance confirmed.
Letter of Instruction
Scope, specific questions, documents to provide, fee agreement, and timetable. See our guide on drafting a letter of instruction.
Provide Documents
Contracts, financial statements, management accounts, correspondence, and any prior quantum assessments. Early document provision reduces costs and improves report quality.
Single Joint Expert (SJE) vs Party-Appointed Expert (PAE)
Under CPR Part 35, both SJE and party-appointed experts owe their primary duty to the court. The choice affects cost, timetable, and how disagreements are resolved before trial.
| Factor | Single Joint Expert (SJE) | Party-Appointed Expert (PAE) |
|---|---|---|
| Appointment | Directed by the court; joint letter of instruction from both parties | Each party instructs their own expert separately |
| Cost | Shared between parties, typically lower total cost | Each party bears own expert's fees, higher in aggregate |
| Report | One report for the court; limited scope for competing models | Separate reports; joint statement narrows issues |
| Best for | Straightforward quantum; proportionate disputes; court-directed | High-value commercial claims; complex multi-head loss analysis |
See also: Party-Appointed Expert (glossary), CPR Part 35 qualifications, how to instruct an expert.
Matching Timeline
- 1Day 1: Submit case details via our contact form
- 2Day 1–2: We identify suitable experts by loss type and sector
- 3Day 2–3: Expert CVs and availability provided for your review
- 4Day 3–5: Letter of instruction agreed and engagement confirmed
- 5Week 2+: Expert commences analysis and report preparation
Red Flags
- Expert who does not understand Hadley v Baxendale remoteness
- No sector experience relevant to the dispute
- Cannot articulate the but-for methodology clearly
- Prior adverse judicial comments on their quantum methodology
- Full-time expert witness with no active practice
Ready to Instruct a Contract Loss Expert Witness?
Submit your case details and we will match you with a qualified forensic accountant, quantum surveyor, or economic damages specialist. Court-ready expert reports. Response within 1 business day.
Instruct an Expert WitnessOr email contact@contractlossexpert.com