Some things or documents -- some things and documents with certain characteristics or appearances -- do not have to be authenticated: some things or documents are "self-authenticating."

Fed. R. Evid. 611(c) ("When a party calls a hostile witness, an adverse party, or a witness identified with an adverse party, interrogation may be by leading questions.").Leading questions can be put to a hostile witness even if the witness was called by the interrogating counsel.

Perry v. Leeke, 488 U.S. 272, 282 (1989) (Court refers to the "truth-seeking function of the trial").The determination of facts and the accurate determination of facts are important purposes of the process of proof and the law of evidence in America.

Ward v. United States, 838 F.2d 182, 187 (6th Cir. 1988) (holding, in plaintiff spouses' medical malpractice action against defendant's surgeon-employee, that the trial court' properly read and relied on Dr. Pulec's....If a treatise, periodical, or similar literature is shown to be reliable and authoritative on a topic, under some circumstances a statement in such literature about the topic falls within an exception to the prohibition against the admission of hearsay evidence.