Does a criminal defendant have to agree to a jury of less than six jurors?

5 Appellant agreed to a jury of six persons. According to Ballew v. Georgia, supra, 435 U.S. 223, 239, 98 S.Ct. 1029, 1038, the state may not try a criminal defendant before a jury of five persons because there is "substantial doubt about the reliability and appropriate representation of panels smaller than six." We do not reach the question whether defense counsel would provide ineffective assistance if he or she counseled a criminal defendant to agree to less than six jurors.