In the UK, assessing mental capacity follows the guidelines set out in the Mental Capacity Act (2005) and its five guiding principles, which help ensure individuals’ rights and autonomy are respected. Understanding the mental capacity assessment process is essential for anyone involved in supporting individuals who may struggle with decision-making.
The first three principles focus on how individuals should be supported and respected to make their own decisions before a lack of capacity is determined. The final two principles provide guidance on making decisions in the best interests of someone who has been found to lack capacity.
The 5 Principles of the Mental Capacity Act (2005)
Presumption of Capacity
Every adult has the right to make their own decisions and must be assumed to have capacity unless proven otherwise. No one should be assumed to lack capacity solely due to factors like age, appearance, diagnosis, or any external characteristic.
Right to Make Unwise Decisions
People have the right to make decisions that may seem unwise or unconventional to others. This principle emphasizes that mental capacity is about the ability to make a decision, not the nature of the decision itself. If the person understands the consequences, they have the right to make choices even if others disagree with them.
Individuals Must Be Supported to Make Their Own Decisions
All practical steps should be taken to support individuals in making their own decisions before concluding they lack capacity. Support might include providing information in an accessible format, allowing extra time, or involving a trusted person to help with understanding and communication.
Best Interests
Any decision or action taken on behalf of someone who lacks capacity must be in their best interests. This involves considering the individual’s past and present wishes, feelings, beliefs, and values, as well as consulting those close to the individual to ensure a well-rounded perspective.
Least Restrictive Option
When making a decision on behalf of someone who lacks capacity, the least restrictive option should be chosen. This ensures individuals retain as much freedom and autonomy as possible, with minimal interference in their rights or freedom.
How to Assess Mental Capacity: The Two-Stage Test
The mental capacity test criteria set out in the Mental Capacity Act involves a structured two-stage test that assesses whether an individual can make a particular decision.
In the landmark case A Local Authority (Respondent) v JB (2021), the Supreme Court clarified the two-stage test outlined in the Mental Capacity Act (2005). Lord Stephens emphasised the importance of a clear sequence in assessing capacity:
"If the court concludes that [the individual] is unable to make a decision for [themselves] in relation to the matter, then the second question that the court is required to address under section 2(1) is whether that inability is 'because of' an impairment of, or a disturbance in the functioning of, the mind or brain." This calls for a "clear causative nexus" between the person’s inability to make a decision and their mental or neurological impairment" (78)
The two questions under section 2(1) are to be approached in that sequence." (79)
This means the functional aspect of the test must be established before determining if the inability is due to a impairment of the mind or brain.
The Mental Capacity Assessment Process: Applying the Two-Stage Test in Practice
The court ruling emphasised a refined approach to the mental capacity assessment process, requiring that the two-stage test be followed carefully.
Stage 1 (Functional Test)Does the individual:
Understand the relevant information for the decision that needs to be made?
Retain the relevant information long enough to make the decision?
Use or weigh the relevant information as part of the decision-making process?
Communicate the decision (verbally, in sign language, or any other means)?
Stage 2 (Diagnostic Test)
If the person cannot make the decision, is this inability due to an impairment or disturbance in the functioning of their mind or brain?
The mental capacity assessment process ensures that individuals’ rights are protected by confirming, in a structured way, whether a person has the capacity to make a specific decision.
This approach, solidified in the A Local Authority v JB judgment, is designed to be thorough and respectful, ensuring that any mental capacity assessment carefully balances support for individual decision-making with safeguards for those who genuinely need assistance in making certain decisions.