(a) Except as provided in division (b) of this section, R.C. § 2929.14(C) or § 2971.03(D) or (E), a prison term, jail term or sentence of imprisonment shall be served concurrently with any other prison term, jail term or sentence of imprisonment imposed by a court of this municipality, the state, another state or the United States. Except as provided in division (b)(2) of this section, a jail term or sentence of imprisonment for misdemeanor shall be served concurrently with a prison term or sentence of imprisonment for felony served in a state or federal correctional institution.
(b) (1) A jail term or sentence of imprisonment for a misdemeanor shall be served consecutively to any other prison term, jail term or sentence of imprisonment when the trial court specifies that it is to be served consecutively or when it is imposed for a misdemeanor violation of R.C. § 2907.322, § 2921.34 or § 2923.131. When consecutive sentences are imposed for misdemeanors under this division, the term to be served is the aggregate of the consecutive terms imposed, except that the aggregate term to be served shall not exceed 18 months.
(2) A jail term or sentence of imprisonment imposed for a misdemeanor violation of R.C. § 4510.14, § 4510.16, § 4510.21 or § 4511.19, or a substantially equivalent municipal ordinance, shall be served consecutively to a prison term that is imposed for a felony violation of R.C. § 2903.06, § 2903.08 or § 4511.19 or a felony violation of R.C. § 2903.04 involving the operation of a motor vehicle by the offender and that is served in a state correctional institution when the trial court specifies that it is to be served consecutively. When consecutive jail terms or sentences of imprisonment and prison terms are imposed for one or more misdemeanors and one or more felonies under this division, the term to be served is the aggregate of the consecutive terms imposed, and the offender shall serve all terms imposed for a felony before serving any term imposed for a misdemeanor.
(R.C. § 2929.41)