20 USC 1406 - Requirements for prescribing regulations

(a) In general 
In carrying out the provisions of this chapter, the Secretary shall issue regulations under this chapter only to the extent that such regulations are necessary to ensure that there is compliance with the specific requirements of this chapter.
(b) Protections provided to children 
The Secretary may not implement, or publish in final form, any regulation prescribed pursuant to this chapter that
(1) violates or contradicts any provision of this chapter; or
(2) procedurally or substantively lessens the protections provided to children with disabilities under this chapter, as embodied in regulations in effect on July 20, 1983 (particularly as such protections related to parental consent to initial evaluation or initial placement in special education, least restrictive environment, related services, timelines, attendance of evaluation personnel at individualized education program meetings, or qualifications of personnel), except to the extent that such regulation reflects the clear and unequivocal intent of Congress in legislation.
(c) Public comment period 
The Secretary shall provide a public comment period of not less than 75 days on any regulation proposed under subchapter II or subchapter III on which an opportunity for public comment is otherwise required by law.
(d) Policy letters and statements 
The Secretary may not issue policy letters or other statements (including letters or statements regarding issues of national significance) that
(1) violate or contradict any provision of this chapter; or
(2) establish a rule that is required for compliance with, and eligibility under, this chapter without following the requirements of section 553 of title 5.
(e) Explanation and assurances 
Any written response by the Secretary under subsection (d) regarding a policy, question, or interpretation under subchapter II shall include an explanation in the written response that
(1) such response is provided as informal guidance and is not legally binding;
(2) when required, such response is issued in compliance with the requirements of section 553 of title 5; and
(3) such response represents the interpretation by the Department of Education of the applicable statutory or regulatory requirements in the context of the specific facts presented.
(f) Correspondence from Department of Education describing interpretations of this chapter 

(1) In general 
The Secretary shall, on a quarterly basis, publish in the Federal Register, and widely disseminate to interested entities through various additional forms of communication, a list of correspondence from the Department of Education received by individuals during the previous quarter that describes the interpretations of the Department of Education of this chapter or the regulations implemented pursuant to this chapter.
(2) Additional information 
For each item of correspondence published in a list under paragraph (1), the Secretary shall
(A) identify the topic addressed by the correspondence and shall include such other summary information as the Secretary determines to be appropriate; and
(B) ensure that all such correspondence is issued, where applicable, in compliance with the requirements of section 553 of title 5.