How are CASA volunteers different from social/case workers?

Social workers are employed by the State of Montana and are sometimes working on as many as 20+ cases as well as working on voluntary plans with families, doing investigations, and maintaining other ongoing related workload. The CASA volunteer has more time and is usually serving only on one and sometimes two cases at a time. They are solely devoted to the wellbeing and advocacy of that one child or family of children. They do not replace the social worker and do not have decision-making authority. The CASA is an independent appointee of the court.