What the rule says
California's Health Care Decisions Law, codified at California Probate Code § 4600 et seq., governs advance directives for medical care. The law consolidates two functions that some other states address through separate documents:
1. Designation of a health care agent. A person to make medical decisions on the principal's behalf when the principal lacks capacity. 2. Instructions for end-of-life care. Statements about preferences for life-sustaining treatment, artificial nutrition and hydration, pain management, and other end-of-life issues.
California Probate Code § 4670 provides a statutory form — the Advance Health Care Directive — that combines both functions into a single document. The principal can complete one or both parts: name an agent, give instructions, or both.
The directive becomes effective when the principal is determined to lack capacity to make health care decisions for themselves. The treating physician makes that determination based on the standards in California Probate Code § 4658.
What the directive can cover
The statutory form addresses several categories of decisions:
- Designation of a primary agent and alternate agents to make health care decisions when the principal lacks capacity - Instructions about end-of-life care, including whether to prolong life by all reasonable means, whether to withdraw treatment in the case of terminal illness or permanent unconsciousness, and other specific preferences - Donation of organs, tissues, or body for transplantation, research, or education - Designation of a primary physician to oversee health care decisions - Specific instructions about pain management, religious considerations, or other personal preferences
The principal can complete the entire form, complete only the agent designation, complete only the instructions, or modify the form's standard language. Custom language is permitted as long as it does not violate the statutory framework.
What happens without an advance directive
If a Californian becomes incapacitated without an advance directive, California's surrogate-decision-maker hierarchy under California Probate Code § 4711 applies. In broad terms, the law allows certain individuals to make health care decisions without specific designation:
- A spouse or domestic partner - An adult child - A parent - An adult sibling - A close friend who has demonstrated knowledge of the patient's wishes and values
The surrogate hierarchy provides a default, but it has limitations:
- Disputes among potential surrogates. When multiple family members disagree, no clear rule resolves the conflict. The hospital may need to seek court guidance. - No designated surrogate available. Some patients have no family or close friends willing to serve. In those cases, court appointment of a guardian or conservator may be required. - Surrogate's authority is more limited than an agent's. A surrogate making decisions without a written directive lacks clear evidence of the patient's preferences. End-of-life decisions involving withdrawal of care are particularly difficult without explicit instructions. - Risk of court involvement. When disputes arise or specific decisions are not clearly within the surrogate's authority, hospitals and physicians may decline to act without court approval, leading to delays during medical crises.
An executed advance directive avoids these problems by giving the agent clear authority and providing the principal's preferences in the principal's own words.
Witnessing and execution requirements
A California advance healthcare directive must be executed with specific formalities under California Probate Code § 4673:
- Signed by the principal - Witnessed by two qualified adults, OR notarized
The witnesses must meet specific qualifications under § 4674: they must be at least 18, competent, and at least one of them must not be a relative or someone entitled to inherit from the principal. A health care provider or employee of a health care provider serving the principal generally cannot serve as the only witness.
For patients in skilled nursing facilities, additional witnessing requirements apply under § 4675, including the requirement that one witness be a patient advocate.
What you can do about it
For California residents:
- Execute the statutory form under California Probate Code § 4670, or a substantially similar document. The statutory form is widely accepted and avoids questions about validity. - Designate a primary agent and at least one alternate. A single agent who is unavailable at the moment of need leaves the directive without an effective decision-maker. - Discuss preferences with the agent. A written directive is more effective when the agent has had explicit conversations about the principal's values and wishes. - Provide copies to the agent, primary physician, and key family members. A directive locked in a file cabinet at home is not useful at a hospital. - Update the directive periodically. Life events — marriage, divorce, death of named agents, changes in health — may warrant updates. - Coordinate with other estate planning. The healthcare directive addresses medical decisions only. A separate financial POA addresses non-medical decisions.
Who this affects most
The advance directive is most consequential for:
- California adults who have not executed any directive and rely on default surrogate authority - Patients facing major medical decisions where the family is divided about treatment - Those at risk of being placed in a skilled nursing facility, where additional formalities apply - LGBTQ+ individuals or others whose chosen family may not be recognized in the default surrogate hierarchy - Anyone with strong preferences about end-of-life care that may differ from default treatment patterns
The advance directive is one of the most personal estate planning documents. It affects medical decisions during crises, often making the difference between care that aligns with the patient's values and care that does not.