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Best Interests

Also known as: Best Interests Decision, Best Interests Assessment

Definition

Best interests is the legal principle under the Mental Capacity Act 2005 that decisions made on behalf of someone who lacks mental capacity must genuinely benefit them and respect their wishes and values.

Understanding best interests is essential for anyone creating a Lasting Power of Attorney, as your attorneys will be legally required to make all decisions using this framework if you lose capacity.

What Does Best Interests Mean?

Best interests is a core principle of the Mental Capacity Act 2005 that protects people who cannot make specific decisions for themselves. Under Section 4 of the Act, any decision made on behalf of someone who lacks mental capacity must be made in their best interests. Importantly, "best interests" is not defined as a fixed concept in law because what's best varies from person to person. Instead, the Act provides a statutory checklist that decision-makers must follow, ensuring decisions are based on the person's unique wishes, values, and circumstances—not simply what others think is best or what's most convenient.

The Section 4 checklist requires decision-makers to avoid discriminatory assumptions based on age, appearance, condition, or behaviour, consider whether capacity might return (can the decision wait?), encourage the person to participate as fully as possible, consider past and present wishes, feelings, beliefs, and values, consult with relevant people like family, carers, and attorneys, and for life-sustaining treatment, not be motivated by a desire to bring about death. For example, Sarah, 78, has advanced dementia and needs surgery. Her doctors must review her medical records showing she previously refused blood transfusions due to religious beliefs, then consult with her daughter (her attorney under a health and welfare LPA) and her care home manager. Even though Sarah cannot currently express her views, they must respect her known beliefs when deciding on treatment.

Who makes a best interests decision depends on the situation. For day-to-day care decisions, it's typically the primary carer. For medical treatment, it's the healthcare professional responsible for the patient's care. For legal and financial matters, it's the attorney appointed under a Lasting Power of Attorney or a deputy appointed by the Court of Protection. David appointed his son James as his attorney under a property and financial affairs LPA. James cannot sell David's house simply because it would be easier to manage smaller assets—James must consider whether David would want to stay in his home, consult with David's other children, and respect David's past wishes about property. If people cannot agree on what's in someone's best interests, the Court of Protection can make a binding decision. All best interests decisions should be documented, including what factors were considered and why the decision was reached.

Common Questions

"When does someone need to make a best interests decision?" A best interests decision is needed when someone lacks mental capacity to make a specific decision for themselves. This could apply to medical treatment, where to live, financial matters, or care arrangements. The decision-maker must follow the Mental Capacity Act 2005 checklist, considering the person's wishes, values, and consulting with family and carers.

"Who can make best interests decisions?" The decision-maker depends on the situation. For day-to-day care decisions, it's usually the primary carer. For medical treatment, it's the healthcare professional. For legal or financial matters, it's the attorney under a Lasting Power of Attorney or a court-appointed deputy. All decision-makers must follow Section 4 of the Mental Capacity Act 2005.

"What happens if people disagree about what's in someone's best interests?" If family members, carers, or professionals cannot agree on a best interests decision, the matter can be referred to the Court of Protection. The court will review the evidence, hear from all parties, and make a legally binding decision based on the Mental Capacity Act principles and what's genuinely in the person's best interests.

Common Misconceptions

Myth: Best interests means doing what the family wants or what the majority agrees on.

Reality: Best interests is about what's right for the person who lacks capacity, based on their wishes, values, and circumstances—not what's convenient for family members or what most people prefer. The decision-maker must consider the person's known wishes and values even if these conflict with what family members want. For example, if someone previously expressed they wanted to stay in their own home, this must be given significant weight even if moving to a care home would be easier for family to arrange.

Myth: Acting in someone's best interests means making the decision I would make if I were in their situation.

Reality: Best interests is about what they would want based on their values and beliefs, not what you would want. The Mental Capacity Act specifically requires decision-makers to consider the person's beliefs and values—religious, cultural, moral, or political—and other factors they would consider if they were able to. This means respecting decisions that you personally disagree with, as long as they reflect the person's authentic wishes and values.

  • Mental Capacity Act: The parent legislation that creates the best interests principle and establishes the Section 4 checklist for decision-making.
  • Lasting Power of Attorney: Attorneys appointed under LPAs must make all decisions in the donor's best interests when the donor lacks capacity.
  • Attorney: The person legally obligated to act in their donor's best interests when making decisions under a power of attorney.
  • Deputyship: Deputies appointed by the Court of Protection must also act in the person's best interests when no LPA exists.
  • Court of Protection: The court that determines best interests when there are disputes or particularly complex decisions requiring judicial oversight.

Need Help with Your Will?

Understanding best interests is essential when creating a Lasting Power of Attorney, as your chosen attorneys will be legally required to make decisions using this framework if you lose capacity. Choosing attorneys who understand and respect your values is one of the most important estate planning decisions you'll make.

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Legal Disclaimer:

This article provides general information only and does not constitute legal or financial advice. WUHLD is not a law firm and does not provide legal advice. Laws and guidance change and their application depends on your circumstances. For advice about your situation, consult a qualified solicitor or regulated professional. Unless stated otherwise, information relates to England and Wales.