In NZ the police can hold someone for the purpose of an assessment. Mental Health Act section 8A (application for assessment under MHA) can be filled in by anyone who is aged 18 and over and they must have seen the person within the last three days. A sec 8b must be (supporting or not supporting the application for assessment) must be done by a Doctor, either a general practitioner, registrar, medical officer of special scale etc. If the Doctor supports the application a duly authorised officer (usually a registered nurse) serves the proposed patient with sec 9 of the MHA which details that they are required to attend an assessment by a psychiatrist at a specified place, also gives the proposed patient their rights under the MHA. Sec 10 is the assessment of the proposed patient by the psychiatrist. If the psychiatrist from the assessment determines that the proposed patient does not meet the criteria (very fixed) of the MHA, they may offer informal admission or the proposed patient can go on their merry way. If the psychiatrist deems that the person meets the criteria of the MHA it then proceeds to sec 11 compulsary 5 day inpatient treatment and assessment. This can be discontinued at any time. The patient must be assessed regularily and if they are still under sec 11 on day five they are reassessed for sec 13 of the MHA which is a compulsary inpatient order for 14 days. The judge does not get involved untill the application is made for either a sec 30 (six month compulsary inpatient) or sec 29 community treatment order, however the info above needs to be implemented before this. Registered nurses anywhere in the hospital setting can apply sec 111 of the MHA for the patient to be held for up to 6 hours for the purpose of assessment under the MHA, this must be followed by an 8A. So NO police cannot place someone in a psychiatric hospital at their discretion but can request the crisis team to assess and can fill in an 8A. This was a very brief attempt to explain.