A Living Will, without more, is not the document most people need. As a threshold goal, most people should have a Health Care Power of Attorney (or Health Care Proxy) that names a trusted person as agent or proxy. A still better alternative is to execute both documents or a single, combined "Advance Directive" that names a proxy and provides guidance about one's wishes.
Unfortunately, because of statutory restrictions or inconsistencies within state law, many practicing attorneys advise clients to execute separate rather than combined documents. State advance directive laws are slowly moving toward acceptance of flexible, combined advance directives, but the states differ significantly in this regard.
The reason for the primary importance of the proxy appointment is simple. Most standardized living will forms are quite limited in what they can accomplish and what conditions they cover.
For example, most provide instructions that apply only if the individual is in a terminal condition or permanently unconscious, yet the majority of health care decisions that need to be made for patients lacking capacity concern questions about day-to-day care, placement options, and treatment options short of "pulling the plug."
Moreover, most boilerplate instructions express fairly general sentiments about not wanting treatments that serve only prolong the dying process. Relatively few people disagree with this sentiment. However, applying it to a particular set of facts is more difficult than at first meets the eye. Virtually no interventions only prolong the dying process. Any intervention can produce multiple consequences, some predictable, some not so predictable. If an aggressive and possibly painful course of treatment will give the patient a 1 in 3 chance of recovering to the point of being able to converse again with loved ones for a least a few more months, is that hope enough to treat aggressively? What if the odds were 1 in 25?
Living will instructions always need interpretation, even when the terminal nature of an illness is clear. An agent or proxy under a health care power of attorney can do precisely that. The proxy, who should know the patient's values intimately, can respond to the actual facts and variables known when an actual health care decision needs to be made. Short of possessing a crystal ball, no one can anticipate the specific and often complicated circumstances fate will place them in.
The proxy acts not only as legal decision-maker, but also as spokesperson, analyzer, interpreter, and advocate.
One caveat: if there is no one close to the individual whom he or she trusts to act as health proxy, then the health care power of attorney should not be used. In this circumstance, the Living Will is safer, despite its limitations.