Tennessee's Odd Rules on the Learned Treatise Exception

Federal Rule of Evidence 803(18) provides an exception to the rule against hearsay for

(18) Statements in Learned Treatises, Periodicals, or Pamphlets. A statement contained in a treatise, periodical, or pamphlet if:

(A) the statement is called to the attention of an expert witness on cross-examination or relied on by the expert on direct examination; and

(B) the publication is established as a reliable authority by the expert’s admission or testimony, by another expert’s testimony, or by judicial notice.

If admitted, the statement may be read into evidence but not received as an exhibit.

Conversely, Tennessee has no direct counterpart to Federal Rule of Evidence 803(18). Why?

Tennessee Rule of Evidence 618 states that

To the extent called to the attention of an expert witness upon cross-examination or relied upon by the witness in direct examination, statements contained in published treatises, periodicals, or pamphlets on a subject of history, medicine, or other science or art, established as a reliable authority by the testimony or admission of the witness, by other expert testimony, or by judicial notice, may be used to impeach the expert witness's credibility but may not be received as substantive evidence.

Meanwhile, Tennessee Rule of Evidence 803(18) is reserved, with the Advisory Commission Comments stating:

Learned treatises can be used to impeach an expert but are not themselves admissible to prove the truth of their contents. No good reason exists to permit hearsay to be taken as true just because it is written in books. F.R.Evid. 803(18) is contra.

This seems odd. First, if we're not taking, say, the rigor mortis section of a medical textbook as true just because it is written in a book, why would it be admissible to impeach a doctor if it contradicts his/her testimony about rigor mortis?

Second, as the federal rule makes clear, learned treatise evidence is not admissible simply because it is text written in a book. Instead, the learned treatise needs to be relied upon by an expert or otherwise established as a reliable authority.

-CM