Missouri’s 120-day programs let a judge send a person to the Department of Corrections for a short period, then release them on probation instead of having them serve the full prison sentence. They are often called “shock” or “treatment” 120s, and they can be an important middle ground between probation and prison.
This guide explains how a 120-day program works under RSMo 559.115, as currently in effect, who is eligible, what happens if the program is not completed, and how a 120-day can fit into a plea or sentencing.
How it works
What is a 120-day program in Missouri?
A short stay in the Department of Corrections, followed by probation if it goes well.
The sentence
The judge imposes a prison sentence and delivers the person to the Department of Corrections, while keeping the power to release them on probation within 120 days of delivery.
The program
The court can recommend a DOC 120-day program. The Department assesses the person and decides placement, which may be a structured cognitive behavioral program or an institutional treatment program, based on the assessment and bed space.
Successful completion
If the Department determines the person successfully completed the program, they are released on probation. The court follows that recommendation unless it finds probation not appropriate, which requires a hearing within 90 to 120 days of delivery.
A court-ordered 120 without a program
The judge can also, on the court’s own motion, grant probation any time within 120 days after delivery, sometimes called “shock” time. The State must be notified and can request a hearing.
Eligibility
Who is eligible for a 120-day program in Missouri?
Most offenders, with specific statutory exclusions.
Under RSMo 559.115.8, probation under this section is not available for certain serious offenses, including second degree murder, first degree rape and sodomy (and the earlier forcible rape and sodomy offenses), first degree statutory rape and sodomy, class A child molestation, class A abuse of a child, predatory sexual offenders, and any offense with a statutory ban on probation or parole.
Beyond the exclusions, whether a 120-day is realistic depends on the judge, the offense, the person’s record, and what is driving the case. A treatment 120 is often considered when substance use is behind the charges.
One more benefit: a person’s first incarceration under this section before release on probation does not count as a previous prison commitment when calculating minimum prison terms later under RSMo 558.019.
If it goes wrong
What happens if you fail a 120-day program?
The court decides between probation and the full sentence.
If the Department of Corrections determines the person did not successfully complete the program, the prosecutor and the court are notified and the person is removed from the program. The court then decides whether to grant probation anyway or to order the sentence executed. The sentence imposed at the start is the one that will be served.
That is why the length of the underlying sentence matters even when everyone expects a 120-day. It is the backstop if things do not go as planned.
Strategy
Is a 120-day program a good deal?
Sometimes. It depends on what the alternatives really are.
For a person facing a real risk of a prison sentence, a 120-day can mean months away instead of years. For a person who could realistically receive probation, an SIS, or a dismissal, accepting time in the Department of Corrections may be a bad trade. A 120-day also usually means a conviction and a prison sentence on the record, even if the person is released on probation.
Whether a 120-day makes sense should be weighed against the strength of the State’s evidence, the defenses available, and the person’s record and goals.
See SIS vs SES in Missouri and Missouri felony classes and sentencing.
FAQ
120-day program questions
What is shock probation in Missouri?
A common name for the court’s power under RSMo 559.115 to release a person on probation within 120 days after delivery to the Department of Corrections, with or without a DOC program.
Who decides which 120-day program I go to?
The judge can recommend a 120-day program, but the Department of Corrections assesses the person and decides the placement based on the assessment and available beds.
Is a 120-day program actually 120 days?
It is built around the 120-day window after delivery to the Department of Corrections. Time before delivery, such as time in county jail awaiting transport, is a separate question.
Can the judge refuse to release me after I complete the program?
Only after a hearing. The court must follow the Department’s recommendation unless it finds probation not appropriate, and it can order the sentence executed only after a hearing within 90 to 120 days of delivery.
Does a 120-day count as a prison commitment?
A person’s first incarceration under RSMo 559.115 before release on probation does not count as a previous prison commitment for calculating minimum prison terms under RSMo 558.019.
See our criminal defense page, or call 573-638-8529.
Talk to us
Know the alternatives before you agree to one.
If a 120-day program has been offered or mentioned in your case, call to talk through whether it is the right fit.
Attorney advertising. The choice of a lawyer is an important decision and should not be based solely upon advertisements. This article is general information about Missouri sentencing law as of October 2026, not legal advice, and it does not create an attorney-client relationship. RSMo 559.115 is scheduled to change effective January 1, 2028, and outcomes depend on the facts of each case.
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