N.Y.C. Charter § 906: Section 906. Relations with city departments and agencies.

So far as practicable and subject to the approval of the mayor, the services of all other city departments and agencies shall be made available by their respective heads to the commission for the carrying out of the functions stated in this chapter. The head of any department or agency shall furnish information in the possession of such department or agency when the commission so requests. The corporation counsel, upon request of the chairperson, may assign counsel to assist the commission in the conduct of its investigative or prosecutorial functions.