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Types of DOT Guidance


To enable the public to better understand the various types of documents that the Department of Transportation (DOT) issues that could provide information on our interpretation of, or policy concerning, our rules, statutes, or technical issues and the extent to which the public may rely on them, we have prepared the following descriptions. To the extent that any of the operating administrations in DOT issue additional types of documents that contain guidance, they have provided descriptions of them on the Web sites (see List of Significant DOT Guidance Documents) where they list their significant guidance documents.  In addition, we have prepared a chart describing in further detail the types of guidance documents issued by DOT's operating administrations.

Preambles.  Preambles to final rules may be relied on by the public.  They resemble “legislative history” documents, though they are perhaps even more authoritative, because they are issued at the time of, and as part of, the final rule signed by the head of the agency or another senior official with delegated authority from the agency head.

Adjudicatory Decisions.  These are binding on the parties to the adjudicatory proceedings and have precedential effect on future parties in similar situations.

Generally Applicable Interpretations or Policy Statements Issued or Approved by the Agency Head (or his or her designee).  These documents have the highest and most reliable level of agency guidance documents.  If they are published in the Federal Register or posted on the agency’s Web site and indexed, they not only may be relied on by the public, but they “may be relied on, used, or cited as precedent by an agency against a party,” pursuant to 5 U.S.C. § 552.  Of course, even these documents may not be treated as binding against a private party; to be binding, they must be issued as legislative rules pursuant 5 U.S.C. § 553 requirements.  The DOT agencies, at a minimum, post all significant guidance documents on the web. 

Letters to Specific Individuals or Entities.  Often in response to requests from individuals or entities, agencies will respond to requests for interpretation of particular regulatory or statutory provisions, sometimes in response to particular factual situations, and generally by letter.  If these guidance documents state that they have been issued or approved by appropriate agency officials in accordance with procedures approved by the head of the agency, they may be relied on by the party to whom they are provided.  The DOT agencies may post the letters on their Web sites to provide helpful information to the general public.  Some DOT agencies may also state on those Web sites that other, similarly situated parties may rely on the letters/guidance documents.  However, such parties must ensure that the factual situations are appropriately similar to justify reliance.

Oral Guidance Statements by Senior Agency Officials.  If there is a record of such statements, including a record that they have been approved by the appropriate agency officials, the guidance may be relied upon by the public.  For example, prepared statements from DOT officials testifying at a Congressional committee hearing should have appropriate senior-level approval.

Other Guidance.  Agency officials at all levels, such as inspectors in the field, try to be helpful when responding to the need for guidance.  The response may be to questions over the telephone, during participation in conferences, visits to manufacturing facilities, etc.  Informal guidance statements of this nature are supposed to incorporate general statements of well-defined law or be based on appropriately approved agency guidance.  Such guidance is not binding on the Government and does not alter the obligation of the public to comply with statutory and regulatory requirements.  However, when a regulated person reasonably relies on the advice of an agency official, we will consider that fact carefully before pursuing any enforcement action and as a mitigating factor if enforcement action is brought.  We also will consider the nature and context of the advice, the role and authority of the official and the importance of the guidance in ensuring safety and meeting other critical goals.  It is especially important to remember that there may be differences of opinion over what was actually said when oral guidance is provided.

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