New York Consolidated Laws, Mental Hygiene Law - MHY § 33.05 Communications and visits

(a) Each patient in a facility shall have the right to communicate freely and privately with persons outside the facility as frequently as he wishes, subject to regulations of the commissioner designed to assure the safety and welfare of patients and to avoid serious harassment to others.  Correspondence addressed to public officials, attorneys, clergymen, and to the mental hygiene legal service shall be unrestricted and shall be sent along promptly without being opened.

(b) The commissioner by regulation shall establish guidelines to insure that patients at facilities have full opportunity for conducting correspondence, have reasonable access to telephones, and have frequent and convenient opportunities to meet with visitors.