If you become incapacitated and can’t speak for yourself, medical decisions fall to someone you’ve legally designated in advance, or, if you haven’t done that, to your closest family member as defined by your state’s law. The exact person depends on whether you’ve set up legal documents, whether family is available, and how urgent the situation is.
How Incapacity Is Determined
Before anyone else takes over your medical decisions, a physician first has to determine that you lack the capacity to make them yourself. This isn’t a simple yes-or-no checkbox. It’s a functional assessment tied to the specific decision at hand. A doctor evaluates whether you can understand the relevant information, weigh risks and benefits, consider alternatives, communicate a clear choice, and maintain consistent logic throughout the conversation.
That evaluation draws on a mental status exam covering your level of consciousness, cognition, thought process, judgment, and insight into your condition. Capacity can be lost temporarily from things like delirium, heavy sedation, or intoxication, or permanently from conditions like advanced dementia or severe brain injury. If the doctor determines you can’t meet those criteria for the decision in front of you, someone else steps in.
If You’ve Named Someone in Advance
The strongest way to control who makes your medical decisions is to designate someone through a healthcare power of attorney (also called a healthcare proxy). This is a legal document in which you name a specific person to make medical choices on your behalf when you can’t. That person’s authority kicks in only when a physician determines you lack capacity, and it covers the full range of healthcare decisions: treatments, procedures, medications, facility transfers, and end-of-life care.
A healthcare power of attorney is different from a living will. A living will is a static document that spells out what treatments you do and don’t want, typically focused on life-sustaining measures like ventilators, feeding tubes, and resuscitation. It’s useful, but it can’t anticipate every medical scenario. A healthcare proxy, by contrast, is a person who can adapt to unexpected situations and make judgment calls on your behalf. Most estate planning attorneys recommend having both.
Requirements for making these documents valid vary by state. Some states require witnesses, others require notarization, and a few have specific rules about who can serve as a witness (your designated proxy usually cannot). California, for example, requires a thumbprint in the notary’s journal. Florida allows a notary to sign on behalf of someone physically unable to write, as long as it’s done in front of two disinterested witnesses. Checking your state’s specific requirements matters, because a document that doesn’t meet them may not hold up.
If You Haven’t Named Anyone
Most people don’t have advance directives. When that’s the case, state law fills the gap through what’s called default surrogate consent. Nearly every state has a statute that lists family members in a priority order, and the hospital works down the list until it finds someone available and willing to serve. The typical hierarchy is:
- Spouse or domestic partner
- Adult child (if multiple adult children, they generally need to agree)
- Parent
- Adult sibling
- Other relatives (varies by state)
The person who steps in under this default system is expected to make decisions based on what you would have wanted, not what they personally prefer. This is called “substituted judgment.” If your wishes aren’t known, the surrogate is supposed to act in your best interest. In practice, this works reasonably well when families agree, but it can become complicated when family members disagree about the right course of action or when relationships are strained. Some states have specific tiebreaking procedures; others leave it to the clinical team to mediate.
What Happens in an Emergency
In a life-threatening emergency where there’s no time to locate a surrogate, doctors don’t wait. The legal principle of implied consent allows physicians to provide stabilizing and lifesaving treatment on the assumption that a reasonable person would want to be saved. This covers situations like cardiac arrest, major trauma, stroke, and severe hemorrhage. Once you’re stabilized, the usual process of identifying a decision-maker picks up again.
This emergency authority has limits. It covers interventions necessary to prevent imminent death or serious harm. It doesn’t extend to elective procedures or decisions that can safely wait until a surrogate is identified.
When No Family or Proxy Exists
Some patients have no advance directive, no spouse, no reachable family, and no close friends who can step in. Hospitals refer to these individuals as “unrepresented” or “unbefriended” patients. This situation is more common than you might expect, particularly among older adults, people experiencing homelessness, and those who have outlived their close relatives.
When this happens, a joint policy from the American Thoracic Society and American Geriatrics Society recommends that hospitals not leave decisions to the treating physician alone. Instead, the institution should convene a diverse, multidisciplinary committee that includes clinicians, ethicists, social workers, and sometimes legal counsel to weigh the options. The committee uses whatever information is available about the patient’s values and preferences, gathered from prior medical records, past conversations with staff, or anyone who has shown care and concern for the patient.
Hospitals are also expected to make a diligent effort to confirm that someone truly has no surrogate before resorting to this process. That means carefully reassessing the patient’s own capacity, searching for distant family or friends, and involving anyone familiar with the patient’s wishes. If a patient is expected to remain incapacitated with ongoing healthcare needs for a long time, the institution may initiate proceedings to appoint a legal guardian.
Court-Appointed Guardianship
Guardianship is the most formal and restrictive option, and courts treat it as a last resort. A judge appoints a guardian only after someone files a petition and proves, by clear and convincing evidence, that the person is incapacitated and that no less restrictive alternative exists. The petition must explain why the person is believed to be incapacitated, specifically that they’re likely to suffer harm because they can’t meet their own needs and can’t recognize the need for help.
The court decides who serves as guardian, and it may not be the person who filed the petition. The judge also defines the scope of the guardian’s authority, which can include medical decisions, living arrangements, care providers, financial management, or some combination. Guardianships can be time-limited or ongoing, and the guardian is accountable to the court for the decisions they make.
This process takes time, often weeks or months, which is why it doesn’t help in acute medical situations. It’s typically pursued when someone will need a long-term decision-maker, such as after a severe stroke, a traumatic brain injury, or in the later stages of dementia when no family proxy is available.
How to Protect Your Preferences
The simplest thing you can do is complete a healthcare power of attorney and a living will while you’re healthy and clearly able to express your wishes. Choose someone you trust who understands your values, especially your feelings about quality of life, pain management, and life-sustaining treatment. Have a candid conversation with that person so they’re not guessing in a crisis.
Give copies of your documents to your designated proxy, your primary care doctor, and any hospital where you regularly receive care. Some states maintain registries where you can file advance directives electronically. If your preferences change after a major life event like a divorce, a new diagnosis, or the death of your proxy, update the documents. An outdated healthcare power of attorney naming an ex-spouse can create exactly the kind of confusion these documents are meant to prevent.