Tenn. Code Ann. § 40-20-201

Notwithstanding any other provision of the law to the contrary, in the event that an offender is sentenced to confinement in the department of correction for six (6) years or less and is committed to the department, the department shall have the authority to place the offender in a special alternative incarceration unit in lieu of confinement in a regular state penal facility. In such a unit the offender shall, at a minimum, be required to participate for a period of ninety (90) days in an intensive regimen of work, exercise, military-type discipline and available treatment programs in accordance with policies and procedures established by the department.