N.Y. State Law § 59-g

§ 59-g. Exemption of property from state taxation. The property so\nconveyed and released to the United States shall be exempted from all\ntaxes, assessments and other charges, which may be levied or imposed\nunder the authority of this state; but the jurisdiction hereby ceded and\nthe exemption from taxation hereby granted shall continue in respect to\nsuch property so long as the same shall remain the property of the\nUnited States and be used for purposes of public defense, and no longer.\n