What's the benchmark?
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One of the most overlooked and misunderstood elements of assessing mental capacity is that of the threshold of understanding
When assessing mental capacity it is important that we don't set our expectations about the required level of understanding too high. Various judgements from the Court of Protection have made it very clear that setting the bar too high makes the MCA unworkable, because it creates an unrealistic criteria, which even a person with capacity would struggle to meet.
So how high do we set the bar, I hear you cry.
In certain scenarios this has been established in law, for example when assessing someone's capacity to have sexual relationships, other times it is left up to the individual to decide. When the threshold has not been previously established in law, from my experience and from discussions with various legal bodies, I believe it is necessary to use the 'average man on the street' test (sometimes called 'The man next to you on the Clapham bus' test).
This simply asks you to consider what level of detail you would expect the average man on the street to know about the particular decision you are being asked to address. When using this 'test' it becomes clear that it is not necessary for the individual to have a solid grasp of all the minute details, but they must be able to grasp the salient facts.
This means that the onus is on the assessor to not only determine exactly what the question is that is to be addressed, but also what information is relevant to the decision being made and what different outcomes the person has to be aware of/to choose from.
Set the bar too high and you risk excluding someone with capacity, set it too low and you deem a person to have capacity when in reality it isn't there.