How to Instruct an Expert Witness: A Guide for Lawyers

This guide on how to instruct expert witness is designed for lawyers, caseworkers, and applicants navigating the process of commissioning expert evidence for asylum cases. Getting instruction right is decisive — well-instructed experts produce well-focused reports; poorly-instructed experts produce generic reports that fail to address the specific case. The instruction process typically takes 30-60 minutes but shapes the entire expert output.[1]

UK CPR Part 35 governs UK expert instruction; US FRE 702 and BIA practice apply in the US; Canadian IRB Rules; EU national procedural rules. The core structure is broadly similar — identify expert, engage, provide instructions, receive report, review — but the details matter.

Stage 1: Identify the Right Expert

The first step is identifying the expert with the right expertise for the specific case. Considerations include the following.[2]

Country specialism — expert must know the specific country. Region specialism — where profile is region-specific (Iranian Kurdish, Honduran Garífuna). Profile expertise — women, LGBTQ+, religious minorities, ethnic minorities. Discipline appropriateness — country expert for country conditions; medico-legal for injury. Tribunal experience — track record of accepted reports. Language fluency — for country experts. Availability — capacity within timeline.

Finding experts — Right to Remain Toolkit (UK), Asylum Aid referrals, university networks, Physicians for Human Rights (US), AILA panels, CCVT/RIVO (Canada), specialised NGO networks (Hengaw, 6Rang, Cattrachas, etc).

Stage 2: Approach the Expert

Initial approach is typically an email to the expert (or their assistant) with:

Brief case summary (2-3 paragraphs). Applicant's country of origin and profile. Procedural stage (initial application, refusal, appeal). Deadline for report. Fee expectations. Legal aid or private funding.

Do not share detailed case documents at this stage. Wait for engagement confirmation.

Stage 3: Engagement Letter

Once the expert confirms availability, a formal engagement letter is exchanged. Contents include:[3]

Scope of work — questions to be addressed. Fee — fixed fee or hourly rate. Timeline — draft delivery and final delivery dates. Cross-examination availability — attendance at hearing. Expert declaration — acceptance of CPR 35 duties (UK). Confidentiality — data protection compliance. Payment terms — invoice timing.

Stage 4: Provide Instructions

The heart of the process — clear instructions produce clear reports. Instructions should include the following elements.[4]

Materials Provided

Applicant's witness statement. Refusal letter (if appeal stage). Screening interview transcript. Substantive interview transcript. Home Office bundle. Supporting evidence bundle.

Specific Questions

Structured questions typically include:

Country conditions relevant to the applicant's profile. Specific risk to the applicant on return. Internal relocation viability. Sufficiency of state protection. Sur place activity risk. Specific issues raised in refusal letter. Any specific points requiring analysis.

Instructions should not lead the expert to particular conclusions. UK CPR 35 requires the expert to give independent opinion; leading instructions undermine credibility.

Stage 5: Expert-Applicant Interview

Many experts prefer to interview the applicant directly to clarify factual matters and assess credibility indicators. Considerations include the following.

Applicant preparation — brief the applicant on what to expect. Interpreter — arrange if needed. Format — in person, video conference, or telephone. Duration — typically 1-2 hours. Solicitor attendance — often useful; discuss with expert. Trauma considerations — for sensitive material.

Stage 6: Draft Review

Experts typically provide a draft report before finalisation. Review should focus on:[5]

Factual accuracy — names, dates, places. Currency — recent events reflected. Missing analysis — questions not fully addressed. Formal compliance — CPR 35 declaration. Bibliography — sources cited.

Do NOT ask the expert to change opinions. Corrections should be limited to factual errors, clarifications, and formal compliance. Attempting to change the expert's opinion damages credibility and may breach CPR 35.

Stage 7: Finalisation and Submission

Final report signed by expert; delivered in agreed format. Steps at finalisation include:

Expert signature and date. Statement of truth. Appendices (CV, bibliography, key sources). Invoice. Confirmation of availability for cross-examination. Formal submission with bundle.

Common Pitfalls

Late instruction — leaving weeks not months. Vague instructions — "please address country conditions". Leading instructions — asking for specific conclusions. Wrong expert — insufficient country/profile specialism. No engagement letter — dispute risk over scope/fee. No expert-applicant interview where warranted. Failure to review draft — factual errors persist. Attempting to change expert opinion.

Funding Considerations

Timeline Planning

Working backwards from deadline:

Finalisation and submission — 1 week before deadline. Draft review — 1 week before finalisation. Expert drafting — 2-4 weeks after interview. Expert-applicant interview — 1-2 weeks after instructions. Instructions provided — immediately after engagement letter. Engagement letter — 1 week after initial approach. Initial approach — 8-12 weeks before deadline.

For appeal cases with fixed hearing dates, instruction should begin as soon as notice of appeal is filed.

The instruction process is where cases succeed or fail. A well-instructed expert produces a report that addresses the specific case in the specific jurisdiction with the specific evidence needed. A poorly-instructed expert produces a generic report that could apply to any case. Time invested in instructions pays in outcomes.
UK practitioner consensus 2026

Conclusion

Correctly instruct expert witness processes require seven stages — identification, approach, engagement, instructions, interview, draft review, finalisation. Typical lead time 6-12 weeks. Cost £2-4k for UK country experts. Legal aid available for in-scope UK cases. Clear instructions matter most — vague instructions produce generic reports. See our companion expert witness guide, expert report contents article, and jurisdictions comparison.