D.C. Code § 21-2221.10: Relationship with other legal documents.

If a patient has a durable power of attorney for health care under subchapter I [of the chapter], or a comparable statute in any other jurisdiction, or another legal document with a substantially equivalent purpose to a durable power of attorney or a MOST Form, the most recent document to have been executed shall govern if any conflict exists between the directives in that legal document and the directives in the patient's MOST Form.