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The 5 Key Principles of the Mental Capacity Act

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The 5 Key Principles of the Mental Capacity Act

The Mental Capacity Act 2005 is a set of laws that were passed by Parliament, which are designed to protect and give power to vulnerable people who lack the mental capacity to make their own decisions. It came into force in England and Wales in 2007. Whilst not perfect, they are significant in safeguarding the lives of people who may lack mental capacity.

The five principles of the Mental Capacity Act

There are five key principles that form the basis of the Act. These principles are of such importance that they are set out at the start, before the legal test to determine if a person lacks mental capacity.

These five principles are:

  1. Presumption of capacity
  2. Support to make a decision
  3. Ability to make unwise decisions
  4. Best interest
  5. Least restrictive

The 4th and 5th principles apply only when a person has been assessed to not have mental capacity for the decision in question. Whilst it is not a principle of the Act, it is key to remember that mental capacity is time and decision specific.

1. Presumption of capacity

The first and most important principle is the presumption of capacity. This means it is assumed that everyone has capacity until proved otherwise. A lack of capacity should not automatically be assumed simply based on a person’s age, appearance, condition or behaviour. Similarly, just because a person has lacked capacity to make a previous decision, this does not necessarily mean they cannot make the decision in question. For example, a lack of capacity to manage finances, does not mean a person lacks capacity to decide where they want to live.

2. Support to make a decision

The supported decision principle requires that all practical steps should be taken, to help the person make the decision themselves before treating them as unable to make the decision. This means in practice it is important to consider how and when the person is being asked to make the decision. Is there a time of day when they are more alert? What is the most appropriate way to communicate with them? Have they been provided with all the relevant information? Can location have an effect? Do they need assistance from someone? Often, we can wrongly think a person does not have capacity, simply because we have not taken the time or effort to explain it in a way they can understand.

3. Ability to make unwise decisions

The third principle states a person is not to be treated as unable to make a decision, merely because they make an unwise decision. This is where the focus of assessing a person’s capacity needs to be based on how the person makes the decision, rather than the decision they make. In effect, the decision itself should be irrelevant. If we base our assessment of capacity on the decision, then we are applying our own or society’s beliefs and values to the decision, not the person’s.

4. Best interest

The fourth principle requires that if a decision is made (or an act done) on behalf of a person who does not have mental capacity, then it must be made (done) in their best interest. There is no specific answer as to what is in a person’s best interest, as every decision is unique to the person and circumstances involved. Unfortunately, there is no legal definition of best interest. There is, however, a procedure set out in s.4 of the Mental Capacity Act which should be followed and will assist when making a best interest decision.

5. Least restrictive

Finally, if a decision is made (or an act done) on behalf of a person who does not have mental capacity, it should ideally be the least restrictive option of the person’s rights and freedoms. Other less restrictive options should be considered and applied if at all possible.

Read about: The 2-stage test for mental capacity

Testing for capacity – a brief overview of the two-stage test

This article has been produced by Ashtons Legal

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