A reproduction of, or substitute for, an original document or item of proof that is offered to establish a particular issue in a legal action.
Secondary evidence is evidence that has been reproduced from an original document or substituted for an original item. For example, a photocopy of a document or photograph would be considered secondary evidence. Another example would be an exact replica of an engine part that was contained in a motor vehicle. If the engine part is not the very same engine part that was inside the motor vehicle involved in the case, it is considered secondary evidence.
Courts prefer original, or primary, evidence. They try to avoid using secondary evidence wherever possible. This approach is called the best evidence rule. Nevertheless, a court may allow a party to introduce secondary evidence in a number of situations. Under rule 1003 of the federal rules of evidence, a duplicate is admissible unless a genuine question is raised as to its authenticity or unless it would be unfair to admit the duplicate in place of the original piece of evidence.
After hearing arguments by the parties, the court decides whether to admit secondary evidence after determining whether the evidence is in fact authentic or whether it would be unfair to admit the duplicate. However, when a party questions whether an asserted writing ever existed, or whether a writing, recording, or photograph is the original, the trier of fact makes the ultimate determination. The trier of fact is the judge if it is a bench trial; in a jury trial, the trier of fact is the jury.
Rule 1004 of the Federal Rules of Evidence lists specific exceptions to the best evidence rule. Under rule 1004, secondary evidence of a writing, recording, or photograph is admissible if (1) all originals are lost or destroyed, unless they were lost or destroyed in bad faith by the party seeking to introduce the secondary evidence; (2) no original can be obtained by judicial process or procedure; (3) the party's opponent in the case has possession of the original and does not produce it after being given sufficient notice that the evidence would be subject to examination at a court hearing; or (4) the original evidence is not closely related to a controlling issue in the case.
Green, Eric D., and Charles R. Nesson, and Peter L. Murray. 2000. Problems, Cases, and Materials on Evidence. 3d ed. Gaithersburg, Md.: Aspen Law & Business.