A person appointing an agent must be mentally and legally competent to appoint an agent. Otherwise, the appointment is voidable. Someone who had been declared NCM (i.e., mentally incompetent) by a Court cannot appoint an agent.
You might consider having a guardian or conservator appointed on behalf of your father. A guardianship or conservatorship is a legal relationship between a competent adult (e.g., guardian or conservator) and a person who is no longer able to make his own responsible decisions (e.g., ward). A guardian or conservator appointed by a court can be authorized to make legal, financial, and health care decisions for the ward. The guardian must regularly report to the court and may be removed if he or she does not adequately take care of the ward and adhere to the guardianship or conservatorship laws.
