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GUIDES

Common flaws in mental capacity reports

A capacity report is weakened by an unclear decision, the wrong legal test, missing support, unexplained functional findings or a missing causal link to an impairment. Review the reasoning and evidence before deciding whether clarification or a fresh assessment is needed.

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Author and Publication

Author: Nellie Supports Ltd

Publication Date: 15/05/2026

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Citation

Civil Procedure Rules, Part 35: Experts and Assessors. Available at: https://www.justice.gov.uk/courts/procedure-rules/civil/rules/part35

Copyright

Copyright © 2026 Nellie Supports Ltd. All rights reserved.

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This article is made available for general information, education and professional reference. It may be downloaded, printed and shared for non-commercial purposes, provided that it is reproduced in full, is not altered in any way, and is properly cited as the work of Nellie Supports Ltd. This material must not be edited, adapted, sold, republished, incorporated into commercial products, or used for commercial training, assessment, report-writing or advisory services without prior written permission from Nellie Supports Ltd.

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This article does not constitute legal advice, clinical advice or a substitute for a decision-specific professional assessment. Where legislation, government guidance, court forms or external professional materials are referred to, those materials remain subject to their own copyright, licensing and re-use terms.

Abstract

A capacity report is weakened by an unclear decision, the wrong legal test, missing support, unexplained functional findings or a missing causal link to an impairment. Review the reasoning and evidence before deciding whether clarification or a fresh assessment is needed. This guide covers the relevant evidence, support, process and limits in England and Wales.

What is on this page

A capacity report is weakened by an unclear decision, the wrong legal test, missing support, unexplained functional findings or a missing causal link to an impairment. Review the reasoning and evidence before deciding whether clarification or a fresh assessment is needed. These weaknesses can justify questions about the opinion, but do not all require the same remedy. Distinguish a material gap from a drafting issue and use the legal test for the decision concerned.

Start with the evidence the decision actually requires

Review the decision and relevant time the report was instructed to address. Check the applicable legal test, sources, support and reasoning. A critical review of a will, gift, residence or financial opinion does not automatically ask whether the person can conduct proceedings; litigation capacity is a separate question where it arises.

Apply the Mental Capacity Act test to this decision

Start by presuming capacity and taking all practicable steps to support the person. An unwise decision does not by itself establish incapacity. For this decision at this time, assess whether the person can understand and retain the relevant information, use or weigh it and communicate a decision by any means. If an ability is absent, explain whether an impairment of, or disturbance in the functioning of, the mind or brain causes that inability. Short retention is enough if it enables the decision.

Identify the relevant information

Identify the information relevant to the decision actually assessed. For litigation, consider the properly framed proceedings as a whole with available legal advice and support; for other decisions, use their own material options and consequences. Check whether the report applies the correct test rather than importing a generic checklist.

Gather evidence before drawing conclusions

The assessment is stronger when the evidence is organised before the conclusion is reached. Useful evidence may include the letter of instruction, pleadings or application documents, solicitor attendance notes, expert evidence, court orders, witness statements and records of the person’s instructions. Where records are missing, contradictory or out of date, the report should say so rather than overstate the certainty of the opinion.

Record practicable steps and communication support

The person should be given a meaningful opportunity to make the decision. This may involve simple language, written summaries, visual aids, additional time, breaks, support with hearing or sight, an interpreter, a familiar setting or a carefully timed appointment. The report should explain what support was tried and whether it helped.

Analyse use and weigh, not just understanding

Check whether the report explains the person’s own reasoning and each relevant ability, rather than only their ability to repeat information. For an MCA opinion, any inability must be causally linked to an impairment or disturbance. Disagreeing with the decision or the expert’s conclusion is not itself an evidential flaw.

Consider risk, pressure and vulnerability carefully

Distinguish a problem in the legal test or evidence from risk, disagreement or vulnerability alone. Consider whether another report concerns the same decision, time and support before treating the conclusions as contradictory. Seek legal advice on the materiality of the concern and any further expert evidence.

What a strong report should contain

A strong report should include the instruction, the specific decision, the legal framework, the relevant information, evidence reviewed, practicable steps, direct assessment findings, functional analysis, causation and a clear conclusion. It should also explain any limitations, such as missing evidence, refusal to engage, fluctuating presentation or the need for further legal advice.

Key takeaway

A critical review should identify a material issue and explain how it affects the opinion. Clarification may resolve a gap; changed circumstances or a substantive methodological problem may require further assessment. The court evaluates expert evidence and decides the legal issues.

Frequently asked questions

Does a diagnosis automatically mean someone lacks capacity?

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.

What evidence is useful for Litigation Critical Review of a Mental Capacity Assessment?

Compare the report against its own file: the instruction, the records cited and the records that existed at the time. Flaws usually surface in the gaps: material not reviewed, support steps not recorded, or findings that do not actually support the stated conclusion.

When is a formal assessment for Litigation Critical Review of a Mental Capacity Assessment useful?

A formal critical review is worthwhile when a potentially flawed report is doing real work: supporting an application, defending a decision or underpinning a settlement. Where the conclusion matters and the reasoning is doubtful, a review tells you whether to rely on it, challenge it or replace it. Can someone have capacity for one decision but not another? Yes. Capacity is decision-specific and time-specific. The assessment must identify each decision and relevant time rather than give a general label.

Related mental capacity assessment pages

The related guides below provide further explanation of the decisions, evidence and legal processes discussed here.

Litigation Critical Review of a Mental Capacity Assessment

CPR Part 35 and expert evidence in capacity disputes

CPR Part 35: A Solicitor's Guide to Instructing a Mental Capacity Expert

Read guide

Practical next steps

Compare the conclusion with the decision, relevant information, support and findings recorded. Ask the author about material gaps; where proceedings are involved, obtain legal advice on clarification, expert permission and any further evidence.

Primary sources and official guidance

Mental Capacity Act 2005

Mental Capacity Act Code of Practice

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