OH · rules
Ohio Evid.R. 601
General Rule of Competency
(A) General rule
Every person is competent to be a witness except as otherwise provided in these rules.
(B) Disqualification of witness in general
A person is disqualified to testify as a witness when the court determines that the person is
any of the following:
(1) Incapable of expressing himself or herself concerning the matter as to be
understood, either directly or through interpretation by one who can understand him
or her;
(2) Incapable of understanding the duty of a witness to tell the truth;
(3) A spouse testifying against the other spouse charged with a crime except
when either of the following applies:
(a) A crime against the testifying spouse or a child of either spouse is
charged;
(b) The testifying spouse elects to testify.
(4) An officer, while on duty for the exclusive or main purpose of enforcing
traffic laws, arresting or assisting in the arrest of a person charged with a traffic
violation punishable as a misdemeanor where the officer at the time of the arrest
was not using a properly marked motor vehicle as defined by statute or was not
wearing a legally distinctive uniform as defined by statute;
(5) A person giving expert testimony on the issue of liability in any medical
claim, as defined in R.C. 2305.113, asserted in any civil action against a physician,
podiatrist, or hospital arising out of the diagnosis, care, or treatment of any person
by a physician or podiatrist, unless all the following apply:
(a) The person testifying is license d to practice medicine and surgery,
osteopathic medicine and surgery, or podiatric medicine and surgery by the
state medical board or by the licensing authority of any state;
(b) The person devotes at least one-half of his or her professional time
to the active clinical practice in his or her field of licensure, or to its
instruction in an accredited school, at either the time the negligent act is
alleged to have occurred or the date the claim accrued;
(c) The person practices in the same or a substantially similar specialty
as the defendant. The court shall not permit an expert in one medical
specialty to testify against a health care provider in another medical
specialty unless the expert shows both that the standards of care and practice
in the two specialties are similar and that the expert has substantial
familiarity between the specialties.
If the person is certified in a specialty, the person must be certified by a board
recognized by the American board of medical specialties or the American board of
osteopathic specialties in a specialty having acknowledged expertise and training
directly related to the particular health care matter at issue.
Nothing in this division shall be construed to limit the power of the trial court to
adjudge the testimony of any expert witness incompetent on any other ground, or
to limit the power of the trial court to allow the testimony of any other witness, on
a matter unrelated to the liability issues in the medical claim, when that testimony
is relevant to the medical claim involved.
This division shall not prohibit other medical professionals who otherwise are
competent to testify under these rules from giving expert testimony on the
appropriate standard of care in their own profession in any claim asserted in any
civil action against a physician, podiatrist, medical professional, or hospital arising
out of the diagnosis, care, or treatment of any person.
(6) As otherwise provided in these rules.
History
Effective Date: July 1, 1980 Amended: July 1, 1991; July 1, 2016; July 1, 2020; July 1, 2021; July 1, 2023 Staff Note (July 1, 1991 Amendment) Rule 601 General Rule of Competency Rule 601(A) Children and mental incompetents Evid.R. 601(A) was amended by deleting “and;” from the end of the rule. This is a technical change only. Rule 601(B) Spouse testifying As adopted in 1980, Evid.R. 601(B) provided that a witness was incompetent to testify against his or her spouse in a criminal case unless the charged offense involved a crime against the testifying spouse or the children of either spouse. The rule was based on the policy of protecting the marital relationship from “dissension” and the “natural repugnance” for convicting a defendant upon the testimony of his or her “intimate life partner.” 8 J. Wigmore, Evidence 216-17 (McNaughton rev. 1961). The important issue is who can waive the rule – the defendant or the witness. Under the old rule, the defendant could prevent his or spouse from testifying. In some situations the policy underlying the rule simply does not apply, but the rule does. For example, if a husband kills his mother-in-law and his wife is a witness, she could be prevented from testifying. This would be true even if they were separated and she desired to testify. Cf. Locke v. State (1929), 33 Ohio App. 445, 169 N.E. 833. The a mendment changes this result, by permitting the wife to elect to testify. The approach is supported by a number of commentators. As McCormick has pointed out: “The privilege has sometimes been defended on the ground that it protects family harmony. But family harmony is nearly always past saving when the spouse is willing to aid the prosecution. The privilege is an archaic survival of a mystical religious dogma and of a way of thinking about the marital relation that is today outmoded.” C. McCormick, Evidence 162 (3d ed. 1984). See also 8 J. Wigmore, Evidence 221 (McNaughton rev. 1961) (“This marital privilege is the merest anachronism in legal theory and an indefensible obstruction to truth in practice.”); Huhn, “Sacred Seal of Secrecy”; The Rules of Spousal Incompetency and Marital Privilege in Criminal Cases (1987), 20 Akron L. Rev. 433. The 1991 amendment does not abolish the spousal incompetency rule. The spouse could not be compelled to testify if he or she did not want to testify. In January 1981, the Supreme Court proposed an amendment that would have deleted Evid.R. 601(B). 54 Oh io Bar 175 (1981). This amendment subsequently was withdrawn. 54 Ohio Bar 972 (1981). The 1991 amendment differs from the 1981 proposal. The 1981 proposal would have abolished the spousal incompetency rule in its entirety, thereby permitting the prosec ution to force the spouse to testify. The 1991 amendment does not permit the prosecutor to force testimony from an unwilling spouse. Moreover, the amendment still leaves the defendant with the protection of the confidential communication privilege, which is recognized in R.C. 2317.02(C) and R.C. 2945.42 and governed by Evid.R. 501. This privilege is not affected by Evid.R. 601(B). Rule 601(D) Medical experts Evid.R. 601(D) was amended to prevent the application of the rule in cases in which a physician, podiatrist, hospital, or medical professional is sued as a result of alleged negligence on the part of a nurse or other medical professional. Some cases have held that a nurse is not competent under Evid.R. 601(D) to testify about the standard of nursing care in such a case. See Harter v. Wadsworth-Rittman (August 30, 1989), Medina App. No. 1790, unreported, motion to certify record overruled (December 20, 1989), 47 Ohio St.3d 715, 549 N.E.2d 170. The amendment limits the rule to claims involving care by a physician or podiatrist, and does not prohibit other medical professionals, including nurses, from testifying as to the appropriate standards of professional care in their field. Also, the requirement that an expert medical witness devote three-fourths of his or her time to active clinical practice or instruction was reduced to at least one- half. The phrase “accredited university” was changed to “accredited school” because some ac credited medical schools are not associated with a university. Staff Note (July 1, 2016 Amendment) Nonsubstantive revisions are made to Evid.R. 601(D) to make clear that the rule applies only to expert testimony as to liability in any medical claim, as defined by R.C. 2305.113, asserted against a physician, podiatrist, or hospital arising out of the diagnosis, care, or treatment of any person by a physician or podiatrist. The rule does not apply to expert testimony for any other medical claims, or for any dental, optometric, or chiropractic claims, as defined by R.C. 2305.113. The structure and provisions of Evid.R. 601(D) are also revised to more- closely resemble the structure of R.C. 2743.43 and to incorporate the provisions of that statute that are not inconsistent with the provisions of the current rule. Pursuant to authority of Article IV, Section 5(B) of the Ohio Constitution, the provisions of R.C. 2743.43 are superseded in their entirety by the amended rule. Staff Note (July 1, 2023 Amendment) Division (B)(5)(b) is amended to clarify the time at which the active clinical practice requirement is needed to qualify the witness as an expert witness, in response to the Supreme Court of Ohio’s ruling in Johnson v. Abdullah, 166 Ohio St.3d 427, 2021-Ohio-3304.
Provenance
- Source
- supremecourt.ohio.gov
- Retrieved
- 2026-09-14
- Edition
- 2026-09-14
- Content hash
6edf4c171fcb450a06e3d7cc20bcfa46b3a1dc9fabda3a12cf5bef6ce9f67199
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