TABLE OF CONTENT
What Every Expert Should Know: Letters of Instruction in Clinical Negligence
Did you know the Compensation Recovery Unit recorded 14,562 clinical negligence cases in 2025–26 across England, Scotland and Wales?
When a clinical negligence claim involves medical questions, the court may need expert evidence to understand issues such as the standard of care, causation, injury and prognosis. A clear set of letters of instruction helps the expert to understand what they have been asked to address. In England and Wales, expert evidence is controlled by the Civil Procedure Rules (CPR). Part 35 of these rules says the duty of an expert is to help the court on matters within their expertise.
This guide explains to you what a letter of instruction to a medical expert should cover, what the expert should check before starting work and why clear instructions can improve the quality of expert evidence.
What Is a Letter of Instruction in Clinical Negligence?
A letter of instruction is a written request from a solicitor or other instructing party asking a medical expert to provide an opinion for a legal case. It gives the expert the background, the questions to answer, the documents to consider and the work required. In clinical negligence claims, the instructions should focus on the medical issues that the expert is qualified to address. They should not ask the expert to decide the legal outcome of the claim.
What Every Clinical Negligence Expert Should Know?
A clinical negligence expert should understand the main medical questions set out in letters of instruction before accepting or preparing the evidence. The exact questions will depend on the speciality of the expert and the facts of the case.
Here we cover key considerations that every clinical negligence expert should know.
1. Breach of Duty
Breach of duty asks whether the care provided fell below the standard reasonably expected of a competent professional in the relevant field. The expert should assess whether the care met the applicable clinical standard, rather than determine legal liability.
2. Causation
Causation asks whether the alleged breach caused the injury or made a material difference to the outcome or not. An expert may need to consider what would probably have happened if the patient had received the right care. The expert should separate the facts from assumptions and explain the medical reasoning behind the conclusion. The letters of instruction should state clearly which alleged acts or omissions require a causation opinion.
3. Condition and Prognosis
The expert may also be asked to describe the current condition of the patient and likely future care. This can include symptoms, functional limits, treatment needs, recovery prospects and the need for future care, depending on the speciality of the expert.
What Should a Letter of Instruction for Clinical Negligence Include?
A strong instruction gives the expert a clear way through the case. The following parts are commonly useful when preparing letters of instruction.
1. Case Information
Letters of instruction should identify the parties, the relevant healthcare provider, the role of the expert and the purpose of the report. They should also provide key dates and enough details to identify the treatment in question.
A letter of instruction to a medical expert should also make clear what type of opinion is required and the deadline for the report.
2. Background to the Proceedings
Letters of instruction should not present the case as an argument for one side. They should give the expert a short and balanced summary of the case. This may include the relevant medical history of the patient, the treatment complained of, the main allegations and the stage reached in the proceedings.
3. Key Issues to be Addressed
Letters of instruction should list the questions the expert must answer. For example, the expert may be asked whether the treatment met the expected standard of care, whether a different course of treatment should have been followed and whether the alleged failure caused or contributed to the injury or not.
A letter of instruction to a medical expert should avoid broad questions that go beyond the speciality of the expert.
4. Specific Instructions for the Expert
Letters of instruction should explain exactly what the expert is being asked to do. This may include reviewing records, examining the claimant, considering another expert’s report or giving an opinion on future conditions. The expert should not be asked to act as an advocate. Under CPR Part 35, the expert’s overriding duty is to the court.
5. Documents and Medical Records
Letters of instruction should list the documents. These may include GP records, hospital notes, referral letters, imaging, laboratory results, operation notes and previous reports. The expert should know if any important records are missing. If this happens, the expert may need to raise this issue and sort it before finalising the report.
6. Required Report Format
Letters of instruction should be in the standard format and any court directions that apply. Under CPR Part 35, an expert report should include the expert’s qualifications, the literature or other material relied on, the substance of material instructions, the range of opinion where relevant, conclusions and the required statement of the expert’s duty to the court.
“The report prepared by the single expert should be the evidence in the case on the issues covered by that expert’s report.” — Lord Woolf,
Retd. Barrister and Judge
How Should an Expert Review a Letter of Instruction?
Before starting the substantive work, as an expert, you should read letters of instruction carefully. In a letter, you should look for points, which we mentioned below.
1. Identify the Questions You Need to Answer
When you are reviewing letters of instruction, make a list of every question. Check that each question falls within your expertise. If a question is unclear, ask the instructing solicitor to clarify it. The letter of instruction to a medical expert should give you a clear task. It should not leave you guessing about the purpose of the report.
2. Analyse The Allegations
When you are reading letters of instruction, read the allegations carefully and identify the clinical acts that you are being asked to assess. Do not assume that every allegation is correct. Remember that your role is to assess the medical evidence independently.
3. Review The Key Evidence
Read the records and other material that relate to each question. Look for evidence that supports your opinion and evidence that may oppose your opinion. CPR Part 35 says that experts should consider all material facts, including those that detract from their opinions.
4. Clarify Any Unclear Instructions
If letters of instruction do not provide enough details, then you must contact the instructing solicitor. You may need clarification about the allegations, the documents, the questions, the scope of your opinion or the deadline.
Why a Clear Letter of Instruction Matters in Clinical Negligence
Clear letters of instruction save time and reduce the risk of an incomplete report. They help the expert to understand the questions, identify the relevant evidence and stay within their area of expertise. They also help the solicitor see whether the report answers the questions that matter to the case or not.
The courts place strong emphasis on independence. CPR 35.3 states that an expert’s duty to the court overrides any obligation to the person who instructed or pays them.
Case Study: When a Letter of Instruction Becomes Critical
A useful real-life example comes from Chris Gutteridge of Exchange Chambers, who described a clinical negligence trial involving a claimant and a defendant who each had their own medical expert on breach of duty. During the trial, Mr Gutteridge asked the judge to order the defendant to disclose the letter of instruction that had been sent to its expert. He also asked for permission to question the expert about the contents of that letter.
The court allowed this. After that, Mr Gutteridge said that the contents of the letter and the answers given by the defendant’s expert changed the course of the trial.
This example shows that experts should make sure their instructions are clear, accurate, balanced and within their expertise. They should also check that the instructions match the questions they are expected to answer.
Conclusion
Letters of instruction play a key role in clinical negligence claims. They tell the expert what the case is about, what questions the expert needs to answer and which documents and evidence should be reviewed. In addition, a good instruction should be clear, balanced and focused. It should remain within the field of the expert and support an independent opinion. Experts should also remember that their duty is to the court. They must consider the evidence fairly and explain any limits in their opinion. At Concise Medico, our experts understand the importance of clear instructions and well-structured medical reports. Speak to our team today to find the right expert for your case.
