... isn't grounds for an involuntary commitment. You have to be mentally ill AND dangerous to yourself or others. The 72-hour hold must be based on dangerousness or "grave disability".
I will say that Indiana is different from Wisconsin in offering that 72 hour hold; here, that decision is made by the facility and the police have nothing to do with it.
http://www.psychlaws.org/LegalResources/StateLaws/Indianastatute.htmIC 12-26-4-1
Law enforcement officers; authority to apprehend and transport mentally ill individuals; charging offenses
Sec. 1. A law enforcement officer, having reasonable grounds to believe that an individual is mentally ill, dangerous, and in immediate need of hospitalization and treatment, may do the following:
(1) Apprehend and transport the individual to the nearest appropriate facility. The individual may not be transported to a state institution.
(2) Charge the individual with an offense if applicable
IC 12-7-2-53
Dangerous
Sec. 53. "Dangerous", for purposes of IC 12-26, means a condition in which an individual as a result of mental illness, presents a substantial risk that the individual will harm the individual or others.
IC 12-7-2-130
Mental illness
Sec. 130. "Mental illness" means the following:
(1) For purposes of IC 12-23-5, IC 12-24, and IC 12-26, a psychiatric disorder that:
(A) substantially disturbs an individual's thinking, feeling, or behavior; and
(B) impairs the individual's ability to function.
The term includes mental retardation, alcoholism, and addiction to narcotics or dangerous drugs.
Chapter 5. Emergency Detention
IC 12-26-5-1
Seventy-two hour detention; written application; contents
Sec. 1. (a) An individual may be detained in a facility for not more than seventy-two (72) hours under this chapter, excluding Saturdays, Sundays, and legal holidays, if a written application for detention is filed with the facility. The individual may not be detained in a state institution unless the detention is instituted by the state institution.
(b) An application under subsection (a) must contain both of the following:
(1) A statement of the applicant's belief that the individual is:
(A) mentally ill and either dangerous or gravely disabled; and
(B) in need of immediate restraint.
(2) A statement by at least one (1) physician that, based on:
(A) an examination; or
(B) information given the physician;
the individual may be mentally ill and either dangerous or gravely disabled