N.Y. Comp. Codes R. & Regs. tit. 14, § 527.11 – Communicating freely with others within and outside the facility.

(a) Residents of facilities or programs operated or licensed by the Office of Mental Health have the right to communicate freely and privately with persons within and outside the facility, subject to the provisions of section 527.12 of this Part.
(b) To assist in the exercise of this right, facilities shall provide residents with reasonable access to stationery and telephones to assist them in freely communicating with others outside the facility.
(c) Residents shall have full opportunity to communicate freely with clergy and with their legal representatives, and these communications shall not be restricted. With respect to other correspondence, there shall be no censorship or restriction of incoming or outgoing letters or packages, except in the following circumstances:
1. (1) To assure the safety and welfare of residents, facilities subject to this Part may institute policies governing possession of contraband. Letters or packages which are reasonably suspected to contain contraband or, in the case of facilities operated by the office, otherwise implicate significant security or safety concerns, shall be processed in accordance with such facility policies.
2. (2) To assure the safety and welfare of residents and avoid harassment to others, any resident whose condition, in the opinion of the treatment team, warrants some selectivity, may have incoming and/or outgoing letters or packages not subject to a facility's contraband policy censored or restricted in accordance with section 527.12 of this Part.
(d) With the exception of mail that is processed or restricted in accordance with subdivision (c) of this section, incoming letters and packages should be delivered sealed and unopened to all residents, and all outgoing letters and packages shall be mailed in a like manner, provided, however, in an individual case where there exists an unanticipated, overriding compelling safety or security concern, the reasons why the letter or package was not delivered sealed or unopened to the resident, and a description of how the matter was handled (e.g., in consultation with the United States Postal Service, or other appropriate security intervention) should be appropriately documented in accordance with facility procedure.