Can someone with dementia still sign a Lasting Power of Attorney?
Often, yes. A dementia diagnosis on its own doesn't automatically mean someone can't make a valid LPA. What matters legally is whether they have capacity for this specific decision, at this specific time, not a diagnosis or a label.
What the law actually requires
Quick summary: Under the Mental Capacity Act 2005, every adult is legally assumed to have capacity unless it's established otherwise. To make a valid LPA, someone needs to be able to understand the information relevant to the decision, retain it long enough to use it, weigh it up, and communicate their decision. A dementia diagnosis doesn't override this presumption on its own, it's the person's actual ability to do those four things, for this specific decision, that matters.
It's also a legal principle that someone can't be treated as lacking capacity simply because they make a decision other people consider unwise. Capacity is about the ability to understand and decide, not about whether the decision matches what someone else would have chosen.
Why a diagnosis alone isn't the same as losing capacity
Capacity is assessed for each specific decision, not as a single global switch that's either on or off. Someone in the earlier stages of a dementia diagnosis may lack capacity for something genuinely complex, like managing a detailed investment portfolio, while still having full capacity to understand what an LPA does, who they want to appoint, and the powers they're granting them.
Capacity can also vary through the day for some people. Good practice, and what we do as a matter of course, is to have these conversations at a time that genuinely suits the person, rather than assuming a single difficult moment reflects their capacity overall.
Who checks capacity, and how
Every LPA includes a certificate provider, an independent person who confirms, at the time of signing, that in their opinion the donor understands the purpose of the LPA and the powers being granted. This can be someone who has known the donor personally for at least two years, or a relevant professional such as a GP, solicitor, or social worker.
Where there's genuine uncertainty following a dementia diagnosis, it's sensible to involve a GP or other healthcare professional to formally assess and confirm capacity before proceeding, as an extra layer of protection for everyone involved, not just a box-ticking exercise.
What if capacity has already been lost?
If someone has genuinely lost the capacity to understand and make this specific decision, an LPA can no longer be created for them, by them or by anyone else. At that point, the only route left is an application to the Court of Protection for a Deputyship, a process that's slower, more expensive, and more restrictive than an LPA would have been.
This is exactly why timing matters so much. If there's any uncertainty following a diagnosis, it's genuinely worth having the conversation sooner rather than later, while there's still a clear window to act. If things feel urgent, our Fast Track LPA service is designed to move things along as quickly as possible without cutting corners on the capacity conversation itself.
Unsure if it's already too late?
We handle these conversations with real care, always speaking directly with the person making the LPA, at their pace, without rushing. Please mention any concerns about capacity when you call.
Please don't wait if you're at all unsure
Call 01934 442030 for a free, no-obligation conversation. We'll discuss the situation honestly before booking anything.
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