N.Y. Mental Hyg. Law § 9.57
A physician who has examined a person in an emergency room or provided emergency medical services at a general hospital, as defined in article twenty-eight of the public health law, which does not have an inpatient psychiatric service, shall be authorized to request that the director of the hospital, or his designee, direct the removal of such person to a hospital approved by the commissioner pursuant to subdivision (a) of section 9.39 of this article, if the physician determines upon examination of such person that such person appears to have a mental illness for which immediate care and treatment in a hospital is appropriate and which is likely to result in serious harm to himself or others, as defined in section 9.39 of this article. Upon the request of the physician, the director of the hospital or his designee, is authorized to direct peace officers, when acting pursuant to their special duties, or police officers, who are members of an authorized police department or force or of a sheriff's department to take into custody and transport any such person. Upon the request of an emergency room physician or the director of the hospital, or his designee, an ambulance service, as defined by subdivision two of section three thousand one of the public health law, is authorized to take into custody and transport any such person. Such person may then be admitted in accordance with the provisions of section 9.39 of this article.
N.Y. Mental Hyg. Law § 9.57