I had mental crisis and brought to mental hospital by police…

Were you charged with anything or given a date for a court appearance?

It sounds as though you may have been taken into custody for psychiatric examination under s.17 on the Ontario Mental Health Act.
Section 17, entitled Action by Police Officer, provides as follows:
17. Where a police officer has reasonable and probable grounds to believe that a person is acting or has acted in a disorderly manner and has reasonable cause to believe that the person,

(a) has threatened or attempted or is threatening or attempting to cause bodily harm to himself or herself;

(b) has behaved or is behaving violently towards another person or has caused or is causing another person to fear bodily harm from him or her; or

(c) has shown or is showing a lack of competence to care for himself or herself,

and in addition the police officer is of the opinion that the person is apparently suffering from mental disorder of a nature or quality that likely will result in,

(d) serious bodily harm to the person;

(e) serious bodily harm to another person; or

(f) serious physical impairment of the person,

and that it would be dangerous to proceed under section 16, the police officer may take the person in custody to an appropriate place for examination by a physician.