Missouri Revised Statutes Title XL. Additional Executive Departments § 632.355. Additional detention or period of outpatient detention and treatment may be ordered, when

1. At the expiration of the ninety-day inpatient commitment period ordered by the court pursuant to section 632.350, the respondent may be detained and treated as an involuntarily inpatient for an additional period of time not to exceed one year or such lesser period of time as determined by the court or may be detained for outpatient detention and treatment for a period of time not to exceed one hundred eighty days; provided, that:

2. Within the ninety-day commitment period, the head of the mental health program may file or cause to be filed, in compliance with the requirements of section 632.330, a petition for a one-year inpatient detention and treatment period or a petition for outpatient detention and treatment for a period not to exceed one hundred eighty days if he or she has reasonable cause to believe that the respondent is mentally ill and as a result presents a likelihood of serious harm to himself or herself or others, and that further detention and treatment is necessary pursuant to an individualized treatment plan prepared by the program and filed with the court. Procedures specified in sections 632.340, 632.345 and 632.350 shall be followed.

3. At the conclusion of the hearing, if the court or jury finds that the respondent, as the result of mental illness, presents a likelihood of serious harm to himself or herself or others, and the court finds that a program appropriate to handle the respondent's condition has agreed to accept him or her, the court shall order that the respondent be detained for involuntary treatment in the least restrictive environment for a period not to exceed one year or for outpatient detention and treatment under the supervision of a mental health program in the least restrictive environment for a period not to exceed one hundred eighty days.