20 U.S. Code § 75 - Authority and functions of the board
The board is authorized to adopt an official seal which shall be judicially noticed and to make such bylaws, rules, and regulations, as it deems necessary for the administration of its functions under this subchapter, including, among other matters, bylaws, rules, and regulations relating to the acquisition, exhibition, and loan of works of art, the administration of its trust funds, and the organization and procedure of the board. The board may function notwithstanding vacancies, and three members of the board shall constitute a quorum for the transaction of business.
In order that the collection of the National Gallery of Art shall always be maintained at a high standard and in order to prevent the introduction therein of inferior works of art, no work of art shall be included in the permanent collection of the National Gallery of Art unless it be of similar high standard of quality to those in the collection acquired from the donor.
The board shall have all the usual powers and obligations of a trustee in respect of all trust funds administered by it and all works of art acquired by it.
The board shall submit to the Smithsonian Institution an annual report of its operations under this subchapter, including a detailed statement of all acquisitions and loans of works of art and of all public and private moneys received and disbursed.