Individual papers focus on situations in which expert opinions combine elements of fact and law, the use of impeachment under Rule 407, and character evidence regarding crimes or acts for which no charges were filed. Additional papers consider the admissibility of testimony of a witness taken during a prior proceeding or an earlier stage of the same proceeding, the distinction between permissive and mandatory presumptions as created by the case of County Court of Ulster County v. Allen, and the testimony of psychological experts in cases involving child sexual abuse. The final papers explain rules relating to the use of expert witnesses, in terms of the use of discovery in preparing to cross-examine an opponent's witness and the need for tactical skills in cross-examination as a result of the courts' liberal application of the Federal Rules of Evidence in decisions regarding the use of expert witnesses. Chapter footnotes.