(1) The defendant and prosecuting attorney, with the consent of the court, may submit the trial of any felony to the court. All other trials of felony cases shall be by jury.(2) A jury in a felony case shall consist of twelve members. However the parties may agree in writing, at any time before the verdict, with the approval of the court, that the jury shall consist of any number less than twelve.(3) When the trial is to a jury, questions of law shall be decided by the court and issues of fact shall be determined by the jury.