Mont. Code Ann. § 72-5-306

Guardianship for an incapacitated person may be used only as is necessary to promote and protect the well-being of the person. The guardianship must be designed to encourage the development of maximum self-reliance and independence in the person and may be ordered only to the extent that the person's actual mental and physical limitations require it. An incapacitated person for whom a guardian has been appointed is not presumed to be incompetent and retains all legal and civil rights except those that have been expressly limited by court order or have been specifically granted to the guardian by the court.