Robomatic:

In Wisconsin, there are two separate and distinct documents, each defined by its own statute, one to create a "Living Will (Declaration to Physicians)" and the other to create a "Durable Power of Attorney for Health Care (what you call a proxy)."

The Living Will has no effect whatsoever unless the patient is determined by two physicians, acting independently, to be "terminal." In that situation, the document acts on its own, not requiring the intervention of a third party or proxy. The document communicates the patient's intentions and desires directly to the physician.

A Durable Power of Attorney for Health Care, on the other hand, becomes effective whenever the patient is determined by two physicians to be "incapacitated" regardless of whether or not there is a terminal condition, or even any active disease at all. The agent (Proxy) under this document is required to attempt to determine the wishes of the patient as best as possible and, failing that, to use any means available to determine what the patient would want in the way of health care (asking the patient, written statements, recollection of prior conversations, whatever . . .) and then to act according to those wishes.