Oklahoma

43A OKL. ST. § 5-207(B)(1). Any peace officer who reasonably believes that a person is a person requiring treatment as defined in Section 1-103 of this title shall take the person into protective custody. 43A OKL. ST. § 5-207(G). The parent, brother or sister who is eighteen (18) years of age or older, child who is eighteen (18) years of age or older, or guardian of the person, or a person who appears to be or states that such person is mentally ill, alcohol-dependent, or drug-dependent to a degree that emergency action is necessary may request the administrator of a facility designated by the Commissioner as an appropriate facility for an initial assessment to conduct an initial assessment to determine whether the condition of the person is such that emergency detention is warranted and, if emergency detention is warranted, to detain the person[.] 43A OKL. ST. § 5-207(A). Any person who appears to be or states that such person is mentally ill, alcohol-dependent, or drug-dependent to a degree that immediate emergency action is necessary may be taken into protective custody and detained as provided pursuant to the provisions of this section. 43A OKL. ST. § 5-207(B). Any peace officer who reasonably believes that a person is a person requiring treatment … shall take the person into protective custody.

43A OKL. ST. § 5-410(A). The following persons may file or request the district attorney to file a petition with the district court, upon which is hereby conferred jurisdiction, to determine whether an individual is a person requiring treatment, and to order the least restrictive appropriate treatment for the person: 1. A treatment advocate[;] 2. The father, mother, husband, wife, grandparent, brother, sister, guardian or child, over the age of eighteen (18) years, of an individual alleged to be a person requiring treatment; 3. A licensed mental health professional; 4. A person in charge of any correctional institution; 5. Any peace officer within the county in which the individual alleged to be a person requiring treatment resides or may be found; or 6. The district attorney in whose district the person resides or may be found. 43A OKL. ST. § 1-103(13)(a). "Person requiring treatment" means a person who because of his or her mental illness or drug or alcohol dependency: (1) poses a substantial risk of immediate physical harm to self as manifested by evidence or serious threats of or attempts at suicide or other significant self-inflicted bodily harm, (2) poses a substantial risk of immediate physical harm to another person or persons as manifested by evidence of violent behavior directed toward another person or persons, (3) has placed another person or persons in a reasonable fear of violent behavior directed towards such person or persons or serious physical harm to them as manifested by serious and immediate threats, (4) is in a condition of severe deterioration such that, without immediate intervention, there exists a substantial risk that severe impairment or injury will result to the person, or (5) poses a substantial risk of immediate serious physical injury to self or death as manifested by evidence that the person is unable to provide for and is not providing for his or her basic physical needs.

43A OKL. ST. § 5-410(C). Petitions filed to determine if an individual should be ordered to assisted outpatient treatment … shall only be filed by a licensed mental health professional employed by the Department of Mental Health and Substance Abuse Services or employed by a community mental health center[.] 43A OKL. ST. § 1-103(20). "Assisted outpatient" means a person who: (a) is eighteen (18) years of age or older, (b) is either currently under the care of a facility certified by the Department of Mental Health and Substance Abuse Services as a Community Mental Health Center, or is being discharged from the custody of the Oklahoma Department of Corrections, (c) is suffering from a mental illness, (d) is unlikely to survive safely in the community without supervision, based on a clinical determination, (e) has a history of lack of compliance with treatment for mental illness that has: (1) prior to the filing of a petition, at least twice within the last thirty-six (36) months been a significant factor in necessitating hospitalization or treatment in a hospital or residential facility, or receipt of services in a forensic or other mental health unit of a correctional facility, or (2) prior to the filing of the petition, resulted in one or more acts of serious violent behavior toward self or others or threats of, or attempts at, serious physical harm to self or others within the last twenty-four (24) months, (f) is, as a result of his or her mental illness, unlikely to voluntarily participate in outpatient treatment that would enable him or her to live safely in the community, (g) in view of his or her treatment history and current behavior, is in need of assisted outpatient treatment in order to prevent a relapse or deterioration which would be likely to result in serious harm to the person or persons as defined in this section, and (h) is likely to benefit from assisted outpatient treatment.