The expert's duty is to the court. That is not a formality. It shapes what the expert can and cannot say, and it is one of the reasons expert evidence carries weight. Solicitors who understand this instruct better and get more useful reports.
What the expert must do
- Address the questions posed, and only those questions.
- Set out the material relied on and any material considered but rejected.
- State clearly where opinion ends and where the evidence supports it.
- Concede the limits of the evidence, honestly.
What the solicitor should provide
A written letter of instruction, the pleadings, the relevant evidence, and any assumptions the expert is invited to make. Vague oral instructions produce vague reports. A tight letter is the single largest lever on report quality.