A special master or master in chancery is an individual appointed by the court to assist with some part of a lawsuit, such as discovery—depositions, written questions, and production of documents—and to make recommendations to the judge on how to resolve related disputes. Courts have held that discovery questions that require extensive examination of highly technical and complex documents by a person having both a technical and a legal background may constitute an exceptional condition sufficient to justify the appointment of a master to supervise such discovery.

In Massachusetts, a special master, sometimes referred to as a master in chancery, is an individual appointed by the court to assist in complex aspects of a lawsuit, such as managing the discovery process. This can include overseeing depositions, handling written questions, and supervising the production of documents. The appointment of a special master is particularly common in cases where the discovery involves highly technical or complex documents that require detailed examination by someone with both technical expertise and legal knowledge. Massachusetts courts may appoint a special master under Rule 53 of the Massachusetts Rules of Civil Procedure when the issues are sufficiently complex and it would be beneficial for the efficient administration of justice. The special master reports to the judge and provides recommendations on how to resolve discovery-related disputes, but the ultimate decisions remain with the judge. The use of special masters is intended to streamline the legal process and provide specialized expertise in cases where the court deems it necessary.