An authentic document or item that is offered as proof in a lawsuit, as contrasted with a copy of, or substitute for, the original.
Primary evidence, more commonly known as best evidence, is the best available substantiation of the existence of an object because it is the actual item. It differs from secondary evidence, which is a copy of, or substitute for, the original. If primary evidence is available to a party, that person must offer it as evidence. When, however, primary evidence is unavailable—for example, through loss or destruction—through no fault of the party, he or she may present a reliable substitute for it, once its unavailability is sufficiently established.