What is Mental Capacity?

Mental capacity is the ability to make decisions. Sometimes decisions are relatively simple and made on a daily basis such as what to wear, what to eat and what to do that day.  Other times, decisions are more complex, made less often and might have legal implications such as agreeing to medical treatment, making a Will or where to live.

In law, there is an underlying assumption that all adults are able to make their own decisions, without interference from others and generally speaking, we go about our daily lives making decisions all the time, reaping the benefits of our decisions or suffering the consequences.  Sometimes we make good (or wise) decisions and other times, not so wise.  Nonetheless, there is an assumption that whatever the consequences, all adults have the mental capacity to make their own decisions.

But what happens if an adult can’t make their own decisions?  It may be a temporary inability, such as the affects of drugs or alcohol, or a longer-term or even permanent inability such as a brain injury or illness that affects a person’s ability to make some or even all decisions.  Whatever the reason, if a person can’t make their own decisions a piece of legislation called the Mental Capacity Act (2005) was introduced to ensure that people have the necessary help when it comes to decision-making. More than that though, the Mental Capacity Act protects people from others assuming that they can’t make decisions based on their age, appearance or an illness they may have such as dementia.

The Mental Capacity Act provides a framework for assessing a person’s mental capacity for most decisions and if a person is assessed as lacking the mental capacity to make a particular decision at a particular time, it provides guidance as to how a decision can be made in the person’s best interests.  It is important to not that if you are next of kin, this provides no legal basis for making a decision for another person.  In all cases, the principles of the Mental Capacity Act must be followed when making a decision for another adult, regardless of your relationship to them.

For some decisions such as; making a will, conducting court proceedings, making a gift, entering into a contract and entering into a marriage, other legal tests apply following judgments in court cases (known as common law tests) and aren’t covered by the Mental Capacity Act.