GUIDES
A useful instruction names the decision and relevant time, explains why capacity is in doubt and supplies the documents and context needed to assess it. Agree support, confidentiality, report purpose, deadlines, cost and follow-up without specifying the answer you want.
Author: Nellie Supports Ltd
Publication Date: 15/05/2026
39 Essex Chambers, Mental Capacity Guidance Note: Carrying out and recording capacity assessments.
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A useful instruction names the decision and relevant time, explains why capacity is in doubt and supplies the documents and context needed to assess it. Agree support, confidentiality, report purpose, deadlines, cost and follow-up without specifying the answer you want. This guide covers the relevant evidence, support, process and limits in England and Wales.
A useful instruction names the decision and relevant time, explains why capacity is in doubt and supplies the documents and context needed to assess it. Agree support, confidentiality, report purpose, deadlines, cost and follow-up without specifying the answer you want. The assessor may need to refine the question with the person instructing. A clear instruction helps, but does not substitute for professional judgement or guarantee report quality.
Instructing a mental capacity assessor means commissioning a formal, decision-specific assessment: identifying the decision in question, choosing a suitable independent professional, supplying the context and records the assessment needs and agreeing the practical arrangements and timescale. Families, solicitors, deputies, attorneys and other professionals can all instruct directly, and the quality of what comes back is set, more than anything else, by the quality of what is sent out.
The instruction's first job is naming the decision or decisions precisely: capacity to make this will, sell this property, grant this LPA, litigate this claim, decide between these residence options. Capacity in general is not assessable and a request framed that way invites an unusable report. Where several decisions are in play, list each, because each carries its own test and its own analysis, and where the true concern is a transaction someone else is driving, say that too, since it shapes how the assessment must be designed.
Match expertise to the decision, the person’s presentation and communication needs and the report’s intended use. Check professional standing where relevant, conflicts and the ability to meet any court requirements. Court of Protection, family and civil proceedings do not all use CPR Part 35.
The letter should state the decision and the test where it is known, the reason capacity is in doubt, the purpose the report will serve and who will rely upon it, the family and professional context including any conflict, the person's communication needs and best times, the timescale and any court dates and the documents enclosed. It should also state what is not known honestly, because an assessor warned of uncertainty designs for it, whilst an assessor given a tidy partial picture inherits its gaps.
Agree which records are relevant and how they can be shared lawfully and securely. Include material that points against the preferred conclusion, known gaps and relevant transaction or court documents. Do not send an entire sensitive file without considering relevance and access arrangements.
Agree a suitable setting, timing and communication support. Offer a private opportunity to speak, while recognising that a trusted supporter or interpreter may help. Manage any interest in the outcome and consider further meetings where the person’s abilities or fatigue require them.
State the true timetable, court deadlines, exchange dates, a deteriorating condition, and ask directly what is achievable, since specialist practices can usually prioritise genuine urgency if told of it at instruction rather than at delivery. A careful assessment can provide useful evidence, but it does not prevent later challenge or determine the court or other decision-maker’s conclusion.
Confirm at instruction that the assessor remains available afterwards: to answer reasonable clarification questions, to respond to Part 35 questions where the report enters proceedings and to advise on reassessment if circumstances change. A capacity report often begins a process, deputyship, registration, completion, approval, rather than ending one, and an assessor who stays available through that process is part of what a good instruction secures.
Define the decision and time, disclose the material context, provide relevant evidence and agree the method, fee, timetable and follow-up. The assessor remains responsible for the opinion and should explain any limits in the instruction or evidence.
No. A diagnosis does not establish lack of capacity. For a decision under the Mental Capacity Act, consider the relevant information and practicable support, then assess understanding, retention, use or weighing and communication by any means. Any inability must be caused by an impairment of, or disturbance in the functioning of, the mind or brain. Will-making has its own legal test.
The instruction letter with the decision defined precisely, records or consent to obtain them, the deadline and intended use, and the practical details: where the person lives, communication needs and who should attend. That is the complete instruction pack.
A formal independent report may be appropriate where genuine doubt, complexity, conflicting evidence or a required form warrants it. Many everyday decisions and some professional enquiries can be assessed without commissioning a paid specialist report.
The related guides below provide further explanation of the decisions, evidence and legal processes discussed here.
Send a focused instruction and relevant documents securely. Include contrary evidence and known gaps, identify any conflict and agree the support, timescale, fee and follow-up before work starts.
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