31 C.F.R. § 1.4 – Public inspection and copying.

(a) In general. Subject to the application of the exemptions and exclusions described in 5 U.S.C. 552(b) and (c), each Treasury bureau shall, in conformance with 5 U.S.C. 552(a)(2), make available for public inspection and copying, or, in the alternative, promptly publish and offer for sale the following information with respect to the bureau:
1. (1) Final opinions, including concurring and dissenting opinions, and orders, made in the adjudication of cases;
2. (2) Those statements of policy and interpretations which have been adopted by the bureau but are not published in the Federal Register;
3. (3) Its administrative staff manuals and instructions to staff that affect a member of the public;
4. (4) Copies of all records, regardless of form or format, which have been released to any person under 5 U.S.C. 552(a)(3), and which the bureau determines have become or are likely to become the subject of subsequent requests for substantially the same records because they are clearly of interest to the public at large. The determination that records have become or may become the subject of subsequent requests shall be made by the Responsible Official (as defined at § 1.1(b)(12)).
5. (5) A general index of the records referred to in paragraph (a)(4) of this section.
(b) Information made available by computer telecommunications. For records required to be made available for public inspection and copying pursuant to 5 U.S.C. 552(a)(2) (paragraphs (a)(1) through (4) of this section) which are created on or after November 1, 1996, as soon as practicable but no later than one year after such records are created, each bureau shall make such records available on the Internet.
(c) Deletion of identifying details. To prevent a clearly unwarranted invasion of personal privacy, or pursuant to an exemption in 5 U.S.C. 552(b), a Treasury bureau may delete information contained in any matter described in paragraphs (a)(1) through (4) of this section before making such matters available for inspection or publishing it. The justification for the deletion shall be explained fully in writing, and the extent of such deletion shall be indicated on the portion of the record which is made available or published, unless including that indication would harm an interest protected by the exemption in 5 U.S.C. 552(b) under which the deletion is made. If technically feasible, the extent of the deletion shall be indicated at the place in the record where the deletion was made.
(d) Public reading rooms. Each bureau of the Department of the Treasury shall make available for public inspection and copying, in a reading room or otherwise, the material described in paragraphs (a)(1) through (5) of this section. Fees for duplication shall be charged in accordance with § 1.7. See the appendices to this subpart for the location of established bureau reading rooms.
(e) Indexes.
1. (1) Each bureau of the Department of the Treasury shall maintain and make available for public inspection and copying current indexes identifying any material described in paragraphs (a)(1) through (3) of this section. In addition, each bureau shall promptly publish, quarterly or more frequently, and distribute (by sale or otherwise) copies of each index or supplement unless the head of each bureau (or a delegate) determines by order published in the Federal Register that the publication would be unnecessary and impractical, in which case the bureau shall nonetheless provide copies of the index on request at a cost not to exceed the direct cost of duplication.
2. (2) Each bureau shall make the index referred to in paragraph (a)(5) of this section available on the Internet by December 31, 1999.