Occasionally, complex disputes arise within the context of traditional litigation or arbitration, which need to be resolved correctly and promptly, so that the remainder of the case can proceed toward resolution without unnecessary delay. On such occasions, the judge or arbitrator may not have the necessary time for precise expertise to address and evaluate the specific details of the "mini dispute". In such circumstances, the judge or arbitrator can appoint (usually with the parties' agreement) a knowledgeable attorney or industry expert, to act as "special master" in investigating, evaluating and resolving that narrower issue, and then issuing a written Determination concerning it, which the parties then can take back to the judge or arbitrator, and the remainder of their dispute can move forward.
Here is an example:
A few years ago I was involved in the dispute where all parties alleged that the other had negligently or intentionally deleted critical data from their computers and hard drives. Reciprocal "spoliation" arguments were asserted. Through working with the parties, it became clear that a forensic data service and protocol was needed, along with chain of custody and budget/extent of information needed concerns. The parties agreed to the selection of the Special Master, the scope of work was detailed and approved by the court. The special master then coordinated the work of the computer data forensics expert, who received the computer hard drives and password/access information, conducted the forensics as agreed, accessed the "lost" data, and provided it to all concerned, under the auspices and supervision of the special master. The case could then proceed, and ultimately was resolved prior to trial.