How to get the most from your instructions to Experts

How to get the most from your instructions to Experts

In May 2019, the discrediting of an unsuitable expert caused a fraud trial against 8 defendants to collapse in spectacular fashion. Ensuring the suitability of an expert is just one of the issues facing those involved in the instruction of experts. In this article, Health and Safety Solicitor Sue Dearden and expert Dr. Richard Brown from Finch Consulting provide insights and tips on how to select and get the most from your instructions to experts which include;

  • Why use an expert at all
  • What to do before instructing an expert
  • What evidence and materials should you provide with instructions to an expert
  • What technical information and guidance should be given.

Why use an expert at all?

Experts have a useful role to perform in a range of situations.

Often forgotten is that they can really help to resolve disputes before they become litigious. Would be litigants in civil cases can agree to seek a view from an expert on a joint instruction and be bound by their decision which can help to resolve and shut down specific issues early.

An informed strategic decision on whether to litigate or to defend can also be made by seeking an expert opinion pre litigation. Want to keep a preliminary view confidential? Ask for the view to be delivered in a call or at a meeting – you can always move to a written report later if the preliminary view is helpful.

During litigation, in civil cases experts can be helpful to opine on issues within their expertise to help the Court in determining key issues. In an injury claim for example this could be views relevant to liability and/or causation and/or value.

In criminal cases an expert’s opinion can help in a health and safety context for example, on the often thorny issue of whether, and if so, how far short of expected standards did the Defendant fall, and the likelihood of injury (high, medium or low)  both of which issues are very relevant to guilt and sentence. Accounting experts can also help with context to turnover and profitability shown in a defendant’s accounts which can help to mitigate sentence.

In all litigated cases whether criminal or civil, it is important to remember that an expert is for the Court’s assistance and the expert’s duties are owed to the Court and not to the party instructing him or her. In litigation, with the Court’s permission, experts can be instructed by a party to litigation or jointly, but in either case, the expert’s duty in the evidence provided, is to the Court.

An expert can also be appointed to advise, suggesting pertinent cross examination questions for example within their area of expertise rather than giving evidence themselves. This is particularly common at inquests where decisions about which witnesses are heard from are a matter solely for the Coroner. An expert can assist with informed specialist questions for experts which the Coroner calls in those circumstances.

Before instructing an expert

Think about what skills and expertise you need. Don’t be afraid to ask for CVs, details of relevant work and publications, and for references if you are using someone you don’t know. At this stage you will need to provide your proposed expert with a brief overview of what has happened and of the issues on which they may be asked for a view so that they can consider and confirm whether the issues are matters on which they are expert. Challenge them and ask questions – the burden is on whoever is issuing the instructions to ensure that the expert is suitably skilled. Try to avoid jack of all trades experts – generalists whose experience doesn’t tally with what they claim to be expert in. Check qualifications, currency of knowledge, and court experience, particularly if you are likely to need your expert in a witness box. Speak to them before committing – are they friendly and engaging, and good communicators?

Ensure you know if your proposed expert generally acts for one side or the other (which, particularly in a civil case, might indicate bias if heavily skewed and diminish their credibility as an independent expert). Conversely, in criminal cases prosecutors rarely go outside their own experts (the HSL in particular) which does not seem to diminish their credibility in the same way, and limits the experience of other experts for the prosecution with a result that balance in the source of instructions is less of an issue.

Check hourly rates. At this stage it is probably unfair to ask what the fees might be as the expert will have no idea of the volume of materials they will need to consider and whether a site visit is necessary (unless they are being asked for a view on a very limited point) but are you happy with the rate suggested given their experience and qualifications, and that the expert has a system for time recording their work in suitable time units. Some do appear very vague about time recording concepts.

There are a number of courses available in both civil and criminal expert work, some of which are accredited. Courses typically cover report writing, relevant legal information for experts and giving oral evidence, including cross examination. If your expert might ultimately be needed to give evidence in Court it is worth checking if they hold any such accreditation. Formal training and competence in being an expert can, in the witness box on occasions, end up being as important as the expert’s subject knowledge.

Check availability. Are you working to a timescale and can the expert meet that timescale not just for the next step, but until the likely end of a matter? They may be free now but communicate about what is likely to be needed going forwards, so that you are factored into the expert’s longer term work pipeline.

Check conflicts and anything that might undermine credibility and impartiality. Explain to the expert who you are acting for, who is on the other side or may be on the other side, who is representing everyone involved (Solicitors and Barristers), what other experts are involved, and ask if there is any potential conflict in relation to those involved or subject matter, that might create a perception of bias, which might preclude them from accepting an instruction, or which might cause you embarrassment later on. You need this information now, not when the expense of a report has been incurred. Having to change experts causes delay and additional cost at best, and at worst can lead to your opponent’s position becoming entrenched as they will assume a switch in expert is due to an unhelpful decision.

If the case is a criminal one, a party introducing expert evidence is required to give notice of anything of which that party is aware which might reasonably be thought capable of undermining the reliability of the opinion, or detracting from the credibility or impartiality of an expert, and under Criminal Procedure Rule 19.2(3)(d) the expert is required to disclose to that party any such matter of which the expert is aware. Examples of matters that must be disclosed are listed in the practice direction and include for example lack of an accreditation or other commitment to prescribed standards where that might be expected, and past adverse judicial comment about their expertise and evidence.

What evidence and materials should you provide with instructions to an expert?

When you are satisfied you have a suitable expert and proceed with an instruction, the expert will then be able to assess how long he or she needs to review materials and deliver what you need (review of materials/site visit/report or oral advice). Be upfront about asking for a clear indication of costs for review and approval BEFORE they start work. Don’t be shy about insisting that this is agreed before the expert proceeds. Think about capping costs to control spend if the expert is reluctant to commit. An experienced expert though should be able to provide an acceptable cost range based on the volume of material.

Think about what the expert needs to see when putting your instructions together. They may need statements of case or a copy of charges to understand context and issues, but be careful about what evidence is sent to your expert. Don’t waste money by sending documents that are irrelevant or which your expert does not need (but would need to read to determine that), and remember that the other party will be entitled to see anything you send to your expert so don’t waive privilege over documents that you want to protect for the time being (such as witness statements or other evidence not yet disclosed). A way of protecting statements may be to extrapolate from them without referring to the written statement in the instructions and asking for a view on “hypothetical” positions which you know is supported from the evidence you hold. Think about whether a site inspection should be arranged – it can be a much quicker and surer way of helping an expert understand the circumstances.

Your instruction letter may also become disclosable to the other side, so keep the language objective and neutral and say nothing that acknowledges vulnerabilities that you do not want others to know about (at least for the time being) or indicates admissions which have not yet been made.

Be clear about what issues you want the expert to consider and ask them to acknowledge any areas in which there is a known range of views, with their view on that range supported by evidence. Be clear about burdens of proof and how certain your expert needs to be in his views. The burden may not be the same for a civil case (which would normally require certainty only on the balance of probability ) as it would for a criminal case (where the burden is normally beyond all reasonable doubt, though the civil not criminal standard is relevant to establishing a section 40 defence of reasonable practicability).

Avoid the temptation to simply throw your file of information and evidence in the direction of an expert and ask for a view. Tell them (normally through questions) what you want them to consider and what questions you have in relation to which issues.

Ask for any opinions to be supported by evidence with full referencing of any authoritative material relied on.

A good expert familiar with his or her duties to the Court will list the information seen which has been relevant to their view but ask that this is done in any event. It is a requirement of the Court rules. Additionally, in criminal cases a prosecution expert witness must, and it is good practice for a defence expert witness to, provide an appendix or separate index of material seen but not used in formulating an opinion – in other words a list of unused material

Be clear with your expert about what you anticipate will happen next. Even an approximate timescale helps the expert in ensuring space is retained to build in his or he ability to handle any further instruction.

Think about asking for a call to discuss the report in draft form before it is finalised. Whilst rarely sought, when a final report is presented, another party can insist on sight of drafts, so you want to avoid significant changes and any suggestion that the final views expressed have in any way been influenced. A call to discuss a draft before it is finalised can ensure all questions are answered and points are clarified.

Ask the expert to be mindful of his or her duty to the Court in Civil or Criminal cases and to be mindful of their duty to advise you if anything changes.

Be courteous and keep your retained experts advised of progress with the case so that they know if they  are likely to be needed again as the case evolves.

What technical information and guidance should be given to an expert?

Professional and experienced experts will normally be aware of their obligations of impartiality and duties to the Court, but instructions ought to provide a link to the rules and guidance for the expert to review, or set them out (e.g. in an accompanying appendix) so that there is no scope for misunderstanding..

Be clear in your instructions which Court Rules are relevant.

In Civil Cases (e.g. compensation claims) this  will be Civil Procedure Rules Part 35.  Rule 35.10 sets out the requirements of an expert report, supported by Practice Direction 35 which identifies a number of requirements with which an expert must comply. The civil rules prescribe verbatim the wording to be used at the end of an expert report and, from October 2020 this will change to read:

“I confirm that I have made clear which facts and matters referred to in this report are within my own knowledge and which are not. Those that are within my own knowledge I confirm to be true. The opinions I have expressed represent my true and complete professional opinions on the matters to which they refer.  I understand that proceedings for contempt of court may be brought against anyone who makes, or causes to be made, a false statement in a document verified by a statement of truth without an honest belief in its truth.”

In the Criminal Courts (e.g. health and safety prosecutions) the relevant rules are contained in Part 19 of the Criminal Procedure Rules supplemented by Criminal Practice Direction V Evidence 19A. The CPS Guidance for Experts on Disclosure, Unused Material and Case Management, whilst directed at prosecution experts, is also essential reading for experts on both sides in criminal cases.

Rule 19.4 sets out what an expert’s report in criminal cases must contain. Requirements include a statement and declaration in substantially the same terms as the Practice Direction which says (at 19B.1)


I understand that my duty is to help the court to achieve the overriding objective by giving independent assistance by way of objective, unbiased opinion on matters within my expertise, both in preparing reports and giving oral evidence. I understand that this duty overrides any obligation to the party by whom I am engaged or the person who has paid or is liable to pay me. I confirm that I have complied with and will continue to comply with that duty.

 I confirm that I have not entered into any arrangement where the amount or payment of my fees is in any way dependent on the outcome of the case.

I  know of no conflict of interest of any kind, other than any which I have disclosed in my report.

I do not consider that any interest which I have disclosed affects my suitability as an expert witness on any issues on which I have given evidence.

 I will advise the party by whom I am instructed if, between the date of my report and the trial, there is any change in circumstances which affect my answers to points 3 and 4 above.

 I have shown the sources of all information I have used.

I have exercised reasonable care and skill in order to be accurate and complete in preparing this report.

 I have endeavoured to include in my report those matters, of which I have knowledge or of which I have been made aware, that might adversely affect the validity of my opinion. I have clearly stated any qualifications to my opinion.

 I have not, without forming an independent view, included, or excluded anything which has been suggested to me by others including my instructing lawyers.

 I will notify those instructing me immediately and confirm in writing if for any reason my existing report requires any correction or qualification.

I understand that:

(a)     my report will form the evidence to be given under oath or affirmation;

(b)     the court may at any stage direct a discussion to take place between experts;

(c)     the court may direct that, following a discussion between the experts, a statement should be prepared showing those issues which are agreed and those issues which are not agreed, together with the reasons;

(d)     I may be required to attend court to be cross-examined on my report by a cross-examiner assisted by an expert.

(e)     I am likely to be the subject of public adverse criticism by the judge if the Court concludes that I have not taken reasonable care in trying to meet the standards set out above.

I have read Part 19 of the Criminal Procedure Rules and I have complied with its requirements.

I confirm that I have acted in accordance with the code of practice or conduct for experts of my discipline, namely [identify the code].

[For Experts instructed by the Prosecution only] I confirm that I have read guidance contained in a booklet known as Disclosure: Experts’ Evidence and Unused Material which details my role and documents my responsibilities, in relation to revelation as an expert witness. I have followed the guidance and recognise the continuing nature of my responsibilities of disclosure. In accordance with my duties of disclosure, as documented in the guidance booklet, I confirm that:

(a)     I have complied with my duties to record, retain and reveal material in accordance with the Criminal Procedure and Investigations Act 1996, as amended;

(b)     I have compiled an Index of all material. I will ensure that the Index is updated in the event I am provided with or generate additional material;

(c)     in the event my opinion changes on any material issue, I will inform the investigating officer, as soon as reasonably practicable and give reasons.

I confirm that the contents of this report are true to the best of my knowledge and belief and that I make this report knowing that, if it is tendered in evidence, I would be liable to prosecution if I have wilfully stated anything which I know to be false or that I do not believe to be true.”



  • Check credentials and expertise
  • Check conflicts and any issue that might undermine credibility
  • Check availability for what is needed
  • Check cost rates


  • Provide clear instructions about what is needed and relevant evidence (but be aware that other parties will be entitled to see what your expert has seen)
  • Think about obtaining and agreeing a cost estimate before work begins
  • Ensure your expert is aware of the relevant Court rules and duties and is aware of the declaration that is needed at the end of his or her report
  • Keep your expert updated as the case progresses, particularly if dates and deadlines changed

For over 25 years, Finch has been recognised as leading providers of litigation support. Informed by our in-house engineering expertise, Finch has a substantial range of Experts with a wide breadth of knowledge of many different areas.

If you have any questions about any of the matters discussed in this article please contact:

[email protected] 07909 682688 or

[email protected] 07714 785459