Legal Question in Criminal Law in Tennessee

If it is a true "one year to serve" then the inmate should serve until his Release Eligibility Date (typically 30%, or 110 days) and then be released onto probation under a provision of law called "Determinate Release."

If it is part of split confinement ("serve one year in jail, followed by XX years on probation") then the actual days the inmate will serve depends on whether or not he earns and retains behavior, work, program or other credits. In some cases, the inmate can fully serve ("flatten") a one year sentence in six to nine months.

The judge is allowed to fix a limit on how much good behavior, work, program or other credits may be earned and retained, and under a recent court decision, may order a period of "split confinement" to be served day-for-day, without credits.