Ohio R. Evid. 102
The purpose of these rules is to provide procedures for the adjudication of causes to the end that the truth may be ascertained and proceedings justly determined. The principles of the common law of Ohio shall supplement the provisions of these rules, and the rules shall be construed to state the principles of the common law of Ohio unless the rule clearly indicates that a change is intended. These rules shall not supersede substantive statutory provisions.
Ohio. R. Evid. 102
Staff Note (July 1, 1996 Amendment)
Rule 102 Purpose and Construction; Supplementary Principles
As originally adopted, Evid. R. 102 referred to the common law of Ohio, but only as a framework for construing the particular rules within the Rules of Evidence. The original text of Rule 102 did not suggest what role, if any, the common law was to have in regard to evidentiary issues as to which the Rules of Evidence were silent.
In the years since Ohio adopted the Rules of Evidence, Ohio has added rules codifying the common law on certain topics that the rules had not addressed. Thus, for example, prior to the adoption of Evid. R. 616 in 1991, the rules contained no rule governing the impeachment of a witness for bias or interest. See Staff Note (1991), Evid. R. 616. Even after the adoption of Rule 616, other rules of impeachment remained unaddressed. See, e.g., Ramage v. Central Ohio Emergency Serv., Inc. (1992), 64 Ohio St. 3d 97, 110 (use of learned treatises for impeachment). Similarly, the rules do not expressly address questions regarding the admissibility of expert opinions on certain subjects. See, e.g., Stinson v. England (1994), 69 Ohio St. 3d 451 (expert opinion on causation is inadmissible unless the opinion is that causation is at least probable).
Omissions such as these occur across the entire body of evidence law. The Rules of Evidence, that is, are not an exhaustive compilation of the rules governing evidence questions, nor are the rules preemptive as to subjects that they do not address. The amendment makes clear in the text of the rule not only that the common law of Ohio provides a framework for construing the content of specific rules, but also that the common law provides the rules of decision as to questions not addressed by specific rules.
In addition, in the portion of the rule that establishes the common law as the basis of interpretation of specific rules, the phrase "common law" was amended to read "principles of the common law." The amendment harmonized the reference with the usage in other rules. See, e.g., Evid. R. 501. In addition, it is intended to acknowledge more clearly the character of the common law as an evolving body of principles and precedents, rather than as a static collection of tightly prescribed rules.