755 ILCS 45/4-5.1: Limitations on who may witness health care agencies.

(a) Every health care agency shall bear the signature of a witness to the signing of the agency. No witness may be under 18 years of age. None of the following licensed professionals providing services to the principal may serve as a witness to the signing of a health care agency:

(1) the attending physician, advanced practice registered nurse, physician assistant, dentist, podiatric physician, optometrist, or psychologist of the principal, or a relative of the physician, advanced practice registered nurse, physician assistant, dentist, podiatric physician, optometrist, or psychologist;

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

(3) a parent, sibling, or descendant, or the spouse of a parent, sibling, or descendant, of either the principal or any agent or successor agent, regardless of whether the relationship is by blood, marriage, or adoption;

(4) an agent or successor agent for health care.

(b) The prohibition on the operator of a health care facility from serving as a witness shall extend to directors and executive officers of an operator that is a corporate entity but not other employees of the operator such as, but not limited to, non-owner chaplains or social workers, nurses, and other employees.