(a) Subject to the provisions of subsection (b) of this Code section, any person who has been indicted for an offense for which the death penalty or life without parole may be imposed may enter a plea of guilty at any time after indictment, and the judge of the superior court having jurisdiction may, in the judge's discretion, sentence the person to life imprisonment or to any other punishment authorized by law for the offense named in the indictment.

(b) Unless the district attorney has given notice that the state intends to seek the death penalty pursuant to the Uniform Rules of the Superior Courts, the judge shall sentence the defendant to life imprisonment. In cases where such notice has been given, the judge may sentence the defendant to death or life without parole only if the judge finds beyond a reasonable doubt the existence of at least one statutory aggravating circumstance as provided in Code Section 17-10-30.