(A) If an indictment or count in an indictment charging a defendant with aggravated murder contains a specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code, the defendant may elect to have the panel of three judges, if the defendant waives trial by jury, or the trial judge, if the defendant is tried by jury, determine the existence of that aggravating circumstance at the sentencing hearing held pursuant to divisions (C) and (D) of section 2929.03 of the Revised Code.

1. (1) If the defendant does not elect to have the existence of the aggravating circumstance determined at the sentencing hearing, the defendant shall be tried on the charge of aggravated murder, on the specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code, and on any other specifications of an aggravating circumstance listed in division (A) of section 2929.04 of the Revised Code in a single trial as in any other criminal case in which a person is charged with aggravated murder and specifications.

2. (2) If the defendant does elect to have the existence of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code determined at the sentencing hearing, then, following a verdict of guilty of the charge of aggravated murder, the panel of three judges or the trial judge shall:

   1. (a) Hold a sentencing hearing pursuant to division (B) of this section, unless required to do otherwise under division (A)(2)(b) of this section;

   2. (b) If the offender raises the matter of age at trial pursuant to section 2929.023 of the Revised Code and is not found at trial to have been eighteen years of age or older at the time of the commission of the offense or raises the matter of the offender's serious mental illness at the time of the alleged commission of the offense pursuant to section 2929.025 of the Revised Code and is found under that section to be ineligible for a sentence of death due to serious mental illness, conduct a hearing to determine if the specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code is proven beyond a reasonable doubt. After conducting the hearing, the panel or judge shall proceed as follows:

      1. (i) If that aggravating circumstance is proven beyond a reasonable doubt or if the defendant at trial was convicted of any other specification of an aggravating circumstance, the panel or judge shall impose sentence according to division (E) of section 2929.03 of the Revised Code.
      2. (ii) If that aggravating circumstance is not proven beyond a reasonable doubt and the defendant at trial was not convicted of any other specification of an aggravating circumstance, except as otherwise provided in this division, the panel or judge shall impose sentence of life imprisonment with parole eligibility after serving twenty years of imprisonment on the offender. If that aggravating circumstance is not proven beyond a reasonable doubt, the defendant at trial was not convicted of any other specification of an aggravating circumstance, the victim of the aggravated murder was less than thirteen years of age, and the offender also is convicted of or pleads guilty to a sexual motivation specification that was included in the indictment, count in the indictment, or information charging the offense, the panel or judge shall sentence the offender pursuant to division (B)(3) of section 2971.03 of the Revised Code to an indefinite term consisting of a minimum term of thirty years and a maximum term of life imprisonment.

(B) At the sentencing hearing, the panel of judges, if the defendant was tried by a panel of three judges, or the trial judge, if the defendant was tried by jury, shall, when required pursuant to division (A)(2) of this section, first determine if the specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code is proven beyond a reasonable doubt. If the panel of judges or the trial judge determines that the specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code is proven beyond a reasonable doubt or if they do not determine that the specification is proven beyond a reasonable doubt but the defendant at trial was convicted of a specification of any other aggravating circumstance listed in division (A) of section 2929.04 of the Revised Code, the panel of judges or the trial judge and trial jury shall impose sentence on the offender pursuant to division (D) of section 2929.03 and section 2929.04 of the Revised Code. If the panel of judges or the trial judge does not determine that the specification of the aggravating circumstance of a prior conviction listed in division (A)(5) of section 2929.04 of the Revised Code is proven beyond a reasonable doubt and the defendant at trial was not convicted of any other specification of an aggravating circumstance listed in division (A) of section 2929.04 of the Revised Code, the panel of judges or the trial judge shall terminate the sentencing hearing and impose sentence on the offender as follows:

1. (1) Subject to division (B)(2) of this section, the panel or judge shall impose a sentence of life imprisonment with parole eligibility after serving twenty years of imprisonment on the offender.
2. (2) If the victim of the aggravated murder was less than thirteen years of age and the offender also is convicted of or pleads guilty to a sexual motivation specification that was included in the indictment, count in the indictment, or information charging the offense, the panel or judge shall sentence the offender pursuant to division (B)(3) of section 2971.03 of the Revised Code to an indefinite term consisting of a minimum term of thirty years and a maximum term of life imprisonment.