Mental Capacity: Why It’s Not Always Clear-Cut
18th August 2025
When it comes to making decisions about health, finances, or legal matters, mental capacity plays a critical role. Whether you’re helping a loved one apply for a Lasting Power of Attorney (LPA) or facing a situation where capacity is in question, one thing quickly becomes clear: determining capacity isn’t always straightforward.
What Is Mental Capacity?
Mental capacity is the ability to make and communicate decisions. Under the Mental Capacity Act 2005, a person is assumed to have capacity unless it’s proven otherwise. The Act defines someone as lacking capacity if they cannot understand, retain, or weigh up relevant information, or communicate their decision.
This sounds clear in theory. In practice, it’s a lot more complex.
The Grey Areas in Capacity Assessments
Capacity can vary day-to-day or even hour-to-hour, especially for those with conditions like dementia, stroke, or mental illness. Someone might be able to decide what they want for lunch, but not manage their bank account. Mental capacity isn’t one-size-fits-all: it’s decision-specific and time-specific.
This nuance can make it difficult for family members and professionals alike to determine when someone truly lacks capacity. The result? Hesitation, disagreement, and in many cases, legal confusion.
Why It Matters for LPAs
One of the biggest challenges comes when it’s time to create a Lasting Power of Attorney. LPAs must be made while the person still has full mental capacity. If that window of time is missed, or if there’s disagreement about whether capacity existed, the LPA could be rejected.
Worse still, families may have to go through the more expensive and time-consuming process of applying to the Court of Protection. This often happens when people leave it too late, hoping to “get around to it” eventually.
Professional Assessments Aren’t Always Accessible
While a formal capacity assessment by a GP or specialist can help, they’re not always readily available, especially during times of crisis. And because capacity can fluctuate, even a professional’s assessment might only apply in that moment.
This unpredictability is one reason Power of Attorney Online encourages early action. Waiting until capacity is questioned is often too late.
The Takeaway: Act Early, Plan Ahead
Capacity is a complex and sensitive issue. Not just medically or legally, but emotionally, too. Families often face tough conversations and difficult decisions. But starting early, while capacity is clear and confirmed, helps avoid complications and ensures your loved one’s wishes are honoured.
