Proxy Decision Making

Proxy decision making (also known as substituted judgment) refers to the use of the legal system to replace one person’s judgment with that of another. This process exists to protect individuals from exploitation while allowing them to retain as much decision-making latitude as possible. Society’s interests are served by preventing persons with mental disabilities from engaging in physically, financially, or otherwise harmful conduct. Different categories of proxy decision making include substitutions for prior judgment (as previously expressed in wills and other advance directives); present judgment (involving current capacity to provide informed consent to treatment or to refuse treatment); and future judgment (concerning projected ability to conduct personal and financial affairs).

In 1540, the Statute of Wills enabled English citizens for the first time to bequeath “real property” such as buildings and land. Within 2 years, this law was amended to invalidate wills by persons who were not “sane.” Modern legal challenges still seek to determine whether the testator (a) understood what it means to make a will, (b) was aware of the nature and extent of his or her property, (c) could describe a rational plan for distributing that property, and (d) could identify the “natural objects of one’s bounty”—meaning the persons one would normally expect to inherit the possessions in question. If such challenges succeed or if it can be proven that the will was substantially affected by another person’s “undue influence,” then a probate court will substitute its judgment for that of the deceased. Psychologists testifying in such proceedings may conduct a psychological autopsy, reflecting all currently available information about the decedent’s cognitive status, medical condition, and interpersonal relationships during the period in question.

In recent years, the law has provided for a range of advance directives that allows persons to preordain specific aspects of their future care. These include living wills (conveying the desire to forgo artificial means of life-sustaining treatment) and health care surrogacy (empowering another person to make general health care decisions in the event of future incapacity). If an advance directive is successfully challenged on the grounds that it was not the product of a rational decision, then the individual’s prior judgment may be set aside.

Substitutions for present judgment may occur when persons are unable or unwilling to provide informed consent to health care services. Typically, medical treatment cannot be delivered unless patients assent to it without coercion, after being provided with an explanation of potential risks and benefits, as well as any available alternatives, in language that the patient is capable of understanding. The Capacity to Consent to Treatment Instrument and the MacArthur Competence Assessment Tool for Treatment are among the instruments psychologists may use to determine a patient’s capacity to provide informed consent.

Persons may be hospitalized for a brief period without their informed consent if a qualified health professional determines that an emergency exists. A petition for lengthier periods of civil commitment may be upheld if the court concludes that, based on a qualifying mental condition, the patient presents a danger of harm to self or others, no less restrictive alternative to hospitalization exists, and the patient may reasonably benefit from the treatment provided in that setting. If patients refuse to provide informed consent to psychiatric medication once they have been civilly committed, the facility may attempt to obtain a separate court order to compel this form of treatment if failure to take such medication will constitute a further danger of harm to self or others. Criminal defendants may not be medicated for the purpose of achieving trial competency without their informed consent, unless the medication in question is medically appropriate, will significantly enhance the likelihood of a fair trial, and represents the least restrictive alternative available to further this purpose.

Substitutions for future judgment may occur as a result of guardianship proceedings, in which a person is alleged to be incapable of making decisions at a later date about a specified range of personal and financial affairs. The court may ultimately appoint a guardian to oversee or prevent the respondent’s participation in activities such as voting, marrying, consenting to medical treatment, driving an automobile, or choosing a place to live. Guardians may also control the respondent’s ability to spend money, sell property, and otherwise make contracts, or this may become the separate responsibility of a court-appointed conservator charged with monitoring solely financial matters. Psychologists participate in such proceedings based on their skill in assessing strengths and weaknesses in each area in question. In the past, courts typically rendered “all-or-none” decisions regarding guardianship, such that respondents found lacking capacity in one or more areas would find all their activities subject to supervision; now, however, most jurisdictions provide for “limited” or “partial” guardianship plans that are tailored to the unique needs of the individual.


  1. Drogin, E. Y., & Barrett, C. L. (2003). Substituted judgment: Roles for the forensic psychologist. In I. B. Weiner (Series Ed.) & A. M. Goldstein (Vol. Ed.), Comprehensive handbook of psychology: Vol. 11. Forensic psychology (pp. 301-312). Hoboken, NJ: Wiley.
  2. Marson, D. C., Huthwaite, J. S., & Hebert, K. (2004). Testamentary capacity and undue influence in the elderly: A jurisprudent therapy perspective. Law and Psychology Review, 28, 71-96.
  3. Mazur, D. J. (2006). How successful are we at protecting preferences? Consent, informed consent, advance directives, and substituted judgment. Medical Decision Making, 26, 106-109.
  4. Parry, J. W., & Drogin, E. Y. (2001). Civil law handbook on psychiatric and psychological evidence and testimony. Washington, DC: American Bar Association.
  5. Volicer, L., Cantor, M. D., Derse, A. R., Edwards, D. M., Prudhomme, A. M. et al. (2002). Advance care planning by proxy for residents of long-term care facilities who lack decision-making capacity. Journal of the American Geriatrics Society, 50, 761-767.

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