Legal Memorandum: Medical literature may not be substantive evidence to support a cause of action

Issue: Under Illinois law, may a court determine that medical literature may be submitted as substantive evidence to support a cause of action?

In Illinois, medical literature cannot be used as substantive evidence, but can be used for purposes of impeachment. Downey v. Dunnington, 384 Ill. App. 3d 350, 382 (2008). The admission of evidence and the scope of cross-examination of expert witnesses rests within the sound discretion of the trial court, whose rulings will not be disturbed absent an abuse of that discretion. Iaccino v. Anderson, 406 Ill. App. 3d 397, 408 (2010). A learned text can be used for impeachment on cross-examination in any of the following three circumstances: (1) the trial court takes judicial notice of the author’s competence; (2) the witness concedes the author’s competence; or (3) the cross-examiner proves the author’s competence by a witness with expertise in the subject matter. Stapleton ex rel. Clark v. Moore, 403 Ill. App. 3d 147, 160 (2010).

There is no requirement that adverse witnesses clearly concede that the test is "authoritative." Instead, recognition that a text is "standard," "well-respected," "a very good book," a "standard book," and "a good source" are indications that the text is authoritative. See Bowman v. University of Chicago Hospitals, 366 Ill.App.3d 577, 587 (2006). The Manual is also used as a textbook which the Stapleton court noted was, although not determinative, an additional indication of authoritativeness in and of itself. Stapleton, 403 Ill.App.3d at 159.

There is no blanket prohibition on an attorney reading the text of an authoritative treatise on cross-examination. For example, and although not expressly adopted […]