Idaho Code § 66-604: Signature — Witnesses.

(1) A declaration is effective only if it is signed by the principal and two (2) competent adult witnesses. The witnesses must attest that the principal is personally known to them, signed the declaration in their presence, appears to be of sound mind, and is not under duress, fraud or undue influence.

(2) The following may not serve as a witness to the signing of a declaration:

(a) The attending physician or mental health service provider or a relative of the physician or provider;

(b) An owner, operator, or relative of an owner or operator of a health care facility in which the principal is a patient or resident; or

(c) A person related to the principal by blood, marriage or adoption.