Tenn. Code Ann. § 40-35-117: Applicability of chapter

(a) All persons who commit crimes on or after November 1, 1989, shall be tried and sentenced under this chapter.

(b) Unless prohibited by the United States or Tennessee constitutions, any person sentenced on or after November 1, 1989, for an offense committed between July 1, 1982, and November 1, 1989, shall be sentenced under this chapter.

(c) For all persons who committed crimes prior to July 1, 1982, prior law shall apply and remain in full force and effect in every respect, including, but not limited to, sentencing, parole and probation.