Make decisions on behalf of someone

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Checking mental capacity

A person may not have mental capacity because of a problem with the way their brain functions, for example:

  • a serious brain injury
  • an illness, such as dementia
  • severe learning disabilities

Mental capacity can come and go (for example, with dementia and some mental illnesses). A person can also recover mental capacity (for example, following a severe stroke).

What you must check

You must check that a person has mental capacity to make a decision at the time it needs to be made.

They can make the decision if they can:

  • understand the information they need - for example, what the consequences will be
  • remember the information for long enough to make the decision
  • weigh up the options and make a choice
  • communicate their decision in any way - for example, by blinking or squeezing a hand

You cannot decide a person lacks mental capacity because you think they’ve made a bad or strange decision.

If the person cannot make a decision at a certain time, they may still be able to:

  • make it at another time
  • make decisions about other things

Do not make a decision for them if it can wait until they can do it themselves.

Get help checking mental capacity

You can ask the person’s doctor or another medical professional to assess their mental capacity.

Follow the Mental Capacity Act code of practice when you check mental capacity.