What is Best Evidence?

Legal Definition
Means the best evideince of which the nature of the case admits, not the highest or strongest evidence which the nature of the thing to be proved admits of: e. g. a copy of a deed is not the best evidence; the deed itself is better. Gilb. Ev. 15; 3 Campb.. 236; 2 Starkey, 473 2 Campb. 605; 1 Esp. 127.

2. The rule requiring the best evidence to be produced, is to be understood of the best legal evidence. 2 Serg. & R. 34; 3 Bl. Com. 368, note 10, by Christian. It is relaxed in some cases, as, e. g. where the words or the act of the opposite party avow the fact to be proved. A tavern keeper's sign avows his occupation; taking of tithes avows the clerical character; so, addressing one as The Reverend T. S." 2 Serg. & R. 440 1 Saund. on Plead. & Evid. 49.
-- Bouviers Law Dictionary
Legal Definition
Primary evidence, as distinguished from secondary; original, as distinguished from substitutionary; the best and highest evidence of which the nature of the case ls susceptible. A written instrument is itself always regarded as the primary or best possible evidence of its existence and contents; a copy or the recollection of a witness, would be secondary evidence. State v. McDonald, 65 Me. 467; Elliott v. Van Buren, 33 Mich. 53, 20 Am. Rep. 668; Scett v. State, 3 Tex. App. 104; Gray v. Pentland, 2 Serg. & R. (Pa.) 34; U. S. Sugar Refinery v. Allis Ch, 56 Fed. 786, 6 C. O. A. 121; Manhattan Malting Ch v. Sweteland, 14 Mont 269, 36 Pan. 84.
-- Black's Law Dictionary
Legal Definition
The best legal evidence the nature of the case will admit of. See 3 Tex. App. 103.
-- Ballentine's Law Dictionary