The purpose of the Office shall be to advise and assist the House of Representatives, and its committees and Members, in the achievement of a clear, faithful, and coherent expression of legislative policies. The Office shall maintain impartiality as to issues of legislative policy to be determined by the House of Representatives, and shall not advocate the adoption or rejection of any legislation except when duly requested by the Speaker or a committee to comment on a proposal directly affecting the functions of the Office. The Office shall maintain the attorney-client relationship with respect to all communications between it and any Member or committee of the House.
2 USC § 281a
Purpose and policy
through Public Law 118-10