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Mental Capacity Act 2005

Also known as: MCA 2005, Capacity Act

Definition

The Mental Capacity Act 2005 is UK legislation establishing a legal framework for making decisions on behalf of adults who lack the mental capacity to make specific decisions for themselves.

The Act shapes how decisions about healthcare, finances, and property are made for vulnerable adults in England and Wales, creating safeguards while preserving autonomy.

What Does Mental Capacity Act 2005 Mean?

The Mental Capacity Act 2005 came into force in 2007, applying to England and Wales. It provides legal protection for adults who cannot make particular decisions due to illness, disability, or brain injury. The Act applies to people who lose capacity during life—from dementia or brain injury—and those lacking capacity from birth. Capacity is decision-specific and time-specific, not "all or nothing." Someone may have capacity for simple decisions but lack capacity for complex financial ones.

Section 1 establishes five statutory principles guiding all decisions. Principle 1: Everyone is assumed to have capacity unless proven otherwise. Principle 2: All practical steps must be taken to help someone decide before concluding they lack capacity. Principle 3: Making an unwise decision alone doesn't prove lack of capacity. Principle 4: Decisions for someone lacking capacity must be in their best interests. Principle 5: Actions must restrict rights and freedoms as little as possible. These principles apply to family members, attorneys, deputies, healthcare professionals, and courts.

The Act establishes key mechanisms for protecting vulnerable people. Lasting Powers of Attorney (LPA) allow individuals to appoint attorneys to make decisions if they lose capacity. The Court of Protection makes decisions for people lacking capacity, appoints deputies, and resolves disputes. Deputies are court-appointed decision-makers when no LPA exists. The Act also enables Advance Decisions to Refuse Treatment and authorizes statutory wills for people lacking testamentary capacity.

The MCA 2005 does NOT govern testamentary capacity for ordinary wills—a critical distinction. Testamentary capacity is assessed using Banks v Goodfellow (1870), which sets a lower threshold than the MCA 2005. This allows elderly people to make wills even if they cannot manage complex finances. If someone lacks testamentary capacity, the Court of Protection can authorize a statutory will under Schedule 2. Wills work alongside LPAs—wills govern what happens after death, LPAs govern decisions during life if capacity is lost.

Common Questions

"What is the Mental Capacity Act 2005 and why does it matter?"

The MCA 2005 provides a legal framework for making decisions on behalf of adults who lack mental capacity for particular decisions. It establishes five key principles, enables Lasting Powers of Attorney, creates the Court of Protection, and protects vulnerable people while empowering them to make their own decisions wherever possible.

"Does the Mental Capacity Act 2005 apply to making wills?"

Not directly. Testamentary capacity is assessed using the common law Banks v Goodfellow (1870) test, not the MCA 2005. However, if someone lacks testamentary capacity, the Court of Protection can make a statutory will under the MCA 2005.

"What are the five statutory principles of the Mental Capacity Act 2005?"

The five principles are: (1) presumption of capacity; (2) right to support in decision-making; (3) unwise decisions don't prove lack of capacity; (4) decisions must be in best interests; and (5) least restrictive option must be chosen.

Common Misconceptions

Myth: "The Mental Capacity Act 2005 determines whether someone can make a will"

Reality: The MCA 2005 does NOT govern testamentary capacity for ordinary wills. Testamentary capacity is assessed using Banks v Goodfellow (1870), which courts confirmed remains "the correct and only test." The threshold is deliberately lower than the MCA 2005 standard. If someone lacks testamentary capacity, the Court of Protection can create a statutory will under Schedule 2.

Myth: "If someone lacks capacity under the Mental Capacity Act, they lack capacity for everything"

Reality: The MCA 2005 establishes that capacity is "decision-specific" and "time-specific." Someone may have capacity for simple decisions but lack capacity for complex ones. Capacity can fluctuate—someone with dementia might have capacity when alert but lack it when tired. Every assessment must relate to a specific decision at a specific time.

  • Mental Capacity: The foundational concept that the MCA 2005 defines and governs through its statutory framework.
  • Lasting Power of Attorney: The primary planning mechanism created by the MCA 2005 for appointing decision-makers.
  • Court of Protection: The specialist court established by the MCA 2005 to make decisions and authorize statutory wills.
  • Deputy: Court-appointed decision-makers created by the MCA 2005 when no LPA exists.
  • Testamentary Capacity: The distinct common law test for will-making, NOT governed by the MCA 2005.

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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.