Capacity to Make Health Care Decisions - Fundamentals - Merck Manuals Consumer Version (2024)

Legal capacity and all the rights that go with it remain in effect until death, unless a court of law has determined a person is legally incapacitated. To establish legal incapacity, a court must determine that a person can no longer manage some or all personal affairs and that court intervention is necessary to protect the person. Doctors cannot determine legal incapacity. The legal proceeding is usually called a guardianship or conservatorship proceeding. Legal requirements for declaring incapacity vary by state. However, the following are typically required:

Health care professionals, even if they think the person is incapable of making a decision, cannot override the person’s expressed wishes unless a court declares the person legally incapacitated. However, a doctor can seek a court's ruling regarding a person's legal incapacity, and a doctor may be asked to testify or provide documentation to the court.

Today, state laws favor the term “incapacity” rather than “incompetency” and define the term as task-specific—that is, every task requires different capabilities to accomplish. For example, a person may be declared legally incapacitated regarding financial affairs, yet still retain legal capacity to make medical decisions or decisions about where to live. A finding of legal incapacity by a court of law takes away all or part of a person’s right to make decisions. Legal incapacity normally results in the appointment of a guardian or conservator to make either some or all decisions for the person.

Increasingly, the least restrictive (most self-reliant) alternative requirement for legal capacity includes consideration of technological assistance or supported decision-making. Technology may help people retain some degree of autonomy (for example, by wearing personal emergency response systems, medical monitors that signal a need for action, or automated medication reminders). Also, at least 20 states recognize formal supported decision-making (SDM) agreements, an alternative to legal guardianship or conservatorship, that allow people with disabilities to keep their rights and their decision-making capacity with support from trusted advisors, such as friends, family, or professionals. SDM agreements should define the elements of a supportive relationship and clearly recognize that the person being supported remains the decision-maker. (See Center for Public Representation: Supported Decision-Making and National Resource Center for Supported Decision-Making.)

Clinical incapacity to make health care decisions is the medical judgment of a qualified doctor or other health care professional who determines a person is unable to do the following:

Like legal capacity, clinical capacity is specific to a particular health care decision and is limited to that decision. A person may have the clinical capacity to make a basic health care decision (for example, receiving IV fluids) but may not be able to decide whether to participate in a clinical trial. Importantly, a person with some decrease in capacity may still have enough capacity to designate a surrogate decision maker Default Surrogate Decision Making If a person is unable to make decisions about personal health care, some other person or people must provide direction in decision making. The general term for such person is surrogate decision... read more . Also, clinical incapacity is not necessarily permanent. People who are intoxicated, delirious, comatose, severely depressed, agitated, or otherwise impaired are likely to lack the capacity to make health care decisions but may later regain that capacity. A person’s ability to carry out a decision is also important for doctors to assess. For example, a person with a broken leg may be able to make decisions (for example, to leave the hospital and manage at home) but be unable to carry them out. Providing the necessary support to carry out a decision becomes an important goal of care.

People with dementia may require an evaluation of their level of cognition, memory, and judgment before their doctors can proceed with medical care. People with mild dementia may think clearly enough to understand discussions with their doctors and make some medical decisions.

A doctor cannot go against a person’s wishes unless a court declares the person legally incapacitated or the person's wishes are medically or ethically inappropriate. If doctors find that a person lacks clinical capacity, they turn to someone with the legal authority to act as substitute decision maker. However, if the person or other appropriate party objects to a particular medical decision or to the determination of clinical incapacity, the courts may become involved. In an emergency, people are presumed to consent to any necessary emergency treatment. This process of making emergency health care decisions for people who cannot make decisions for themselves is rarely litigated in court.

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.