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Researching Environmental Law: Regulations and Interpretive Rules

Regulations v. Rules

The terms "regulation" and "rules" are important concepts that are not always straightforward. An understanding of the distinction between them and the roles they play are crucial.

The Administrative Procedure Act (APA) authorizes federal agencies to promulgate rules. The APA defines a “rule” as “an agency statement of general or particular applicability and future effect designed to implement, interpret, or prescribe law or policy.” Let’s take a look at two kinds of rules: legislative and interpretive, neither of which is expressly defined by the APA.

The Supreme Court has said that a legislative or “substantive” rule – commonly referred to as a “regulation” – “binds” the public, and, like a statute, has the “force and effect” of law. The APA generally requires that, to become effective, a legislative rule must go through what is known as notice-and-comment rulemaking – a lengthy process in which the public is given an opportunity to comment on a proposed version of the rule and the agency responds to the comments. The public-comment process sometimes significantly influences the content of legislative rules.

Interpretive rules are treated differently. The APA provides that the notice-and-comment requirement “does not apply” to interpretive rules, and, thus, agencies may issue interpretive rules without any public input. It is often said that an interpretive rule differs from a legislative rule because it does not bind the public or have the force and effect of law, but only states the agency’s interpretation of its governing law or regulations. Interpretive rules include many agency pronouncements, issued with varying indicia of formality, such as guidance documents and interpretive bulletins and memos. Federal agencies operate under thousands of interpretative rules that do not go through notice-and-comment rulemaking.

Brian Wolfman and Bradley Girard, Argument preview:The Administrative Procedure Act, notice-and-comment rule making, and “interpretive” rules, SCOTUSblog (Nov. 26, 2014, 10:13 AM), See 5 U.S.C.A. 552(a)(1)-(2) (West, Westlaw through Pub. L. No. 114-254). 

Making Regulations

Regulations are substantive agency rules with the force and effect of law developed in accordance with the Administrative Procedure Act and an agency's enabling legislation. Administrative rulemaking is primarily done through "notice-and-comment rulemaking": generally, an agency drafts rules, publishes a notice in the Federal Register to announce the proposed rule and solicit public feedback (comments). 

If you are interested in learning more about administrative procedure:

  • A step-by-step look at the process is available here (PDF download) from the Office of the Federal Register
  • The CALI Lessons on administrative law are very helpful. Loyola community members can pick up an access code at the library's circulation desk on the first floor.

Finding Proposed Regulations

Regulations.Gov is one of the best places to find related regulatory information. "The types of documents that can be found on this site include Proposed Rules, Rules, as well as Notices from the Federal Register – often referred to just as “Notices.” Public Submissions (e.g., comments, citizen petitions, early submissions) and Supporting Materials often associated with regulatory actions can also be found on this site." This website is a partnership between multiple federal agencies to allow electronic notice and comments, called the "eRulemaking Program."

  • Monitor federal regulations on - You can search/browse documents by date, agency, and topic and set email alerts for particular dockets.

  • Monitor the Federal Register on - You can check search/browse documents by date, agency, and topic and set up email or RSS subscriptions. These subscriptions offer different options: you can receive the daily table of contents for the Register, get updates on particular topics and agencies, or customize a subscription. The Federal Register is released every day and arranged in chronological order.

Note on Louisiana

As seen on the Environmental Legal System page of this LibGuide, Louisiana has some of its own environmental regulations and guidance. Because the state system is based on on the federal model, much of the information can be found in the same way. Louisiana regulations are available on:

*You can also sign up for update notifications. 

Finding Finalized Regulations

Finalized regulations are published in the Code of Federal Regulations (CFR). The CFR is re-printed once a year and is organized by subject. More information on the CFR and its relationship to the United States Code can be found on the website of the U.S. Government Publishing Office.

Because regulations are laws, they can be found in many places, free and subscription, and in online and print formats. The best place to find and research regulations depends on your resources and what you are looking for. 

Print materials can be more difficult to navigate. Although the print CFR comes with some very helpful tools for research, there is no denying the ease of use for online sources. When we say there are A LOT of regulations on environmental law, we mean A LOT. Title 40 Protection of Environment takes up almost two full shelves all by itself.


One of the best resources is the eCFR from the Legal Information Institute (LII) at Cornell Law School. This is a great resource because it organizes the text to make it easier to read, and it tracks all proposed rules and updates with links to Regulations.Gov published since the last re-printing of the entire title.  As discussed on the Environmental Legal System page, environmental-related regulations are not found within one title of the CFR, but here is an example of this tool using Title 40:

LLI also provides references to the eCFR published by the U.S. Government Publishing Office. This eCFR will also include updates, but it is less user-friendly in that respect.

Regulations are often re-printed on agency websites, will be available in the local library, and available on legal subscription databases (like Westlaw, Lexis Advance, Bloomberg Law, and Fastacse).

Guidance Documents - Interpretative Rules

A excellent article to put guidance documents and environmental issues in perspective is: Sam Kalen, Changing Administrations and Environmental Guidance Documents, 23 Nat. Resources & Env't 13, available on HeinOnline


What are guidance documents?

Remember that federal agencies may issue interpretive rules that do not have the force of law. These rules represent the agency's interpretation of legislative rules (aka regulations) and are not required to be published in the Federal Register. This can make these types of documents more difficult to find. These are known as guidance documents

Guidance documents may also be known as: "interpretive memoranda, policy statements, guidances, manuals, circulars, memoranda, bulletins, advisories, and the like." 72 Fed. Reg. 3432, 3434 (OMB, Jan. 25, 2007). These can be used to help interpret regulations or ensure consistency between agency employees. Unfortunately, these documents can be difficult to find and identify, and although they are useful, there is no required legal procedure for creating them as there is for regulations. 

"The phenomenon we see in this case is familiar. Congress passes a broadly worded statute. The agency follows with regulations containing broad language, open-ended phrases, ambiguous standards and the like. Then as years pass, the agency issues circulars or guidance or memoranda, explaining, interpreting, defining and often expanding the commands in the regulations. One guidance document may yield another and then another and so on. Several words in a regulation may spawn hundreds of pages of text as the agency offers more and more detail regarding what its regulations demand of regulated entities. Law is made, without notice and comment, without public participation, and without publication in the Federal Register or the Code of Federal Regulations." Appalachian Power Co. v. EPA, 208 F.3d 1015, 1019 (D.C. Cir. 2000). 

In 2007, the Office of Management and Budget published "Final Bulletin for Agency Good Guidance Practices" outlining best practices for agencies to follow in publishing guidance documents in an effort to make these documents more procedurally sound and well-defined. The bulletin focuses on "significant" guidance documents and requests that agencies make significant guidance documents available online and provide a chance for public comment. Further, drafts of economically significant guidance documents should be published in the Federal Register and be subject to notice and comment. The Bulletin provides definitions for these terms. 72 Fed. Reg. 3432. Note that this Bulletin refers to an executive order that has since been revoked, but the Bulletin was still posted on the Obama White House website and not rescinded so it seems to be in effect. See Mary Whisner, Some Guidance About Federal Agencies and Guidance, 105 Law Libr. J. 385, 394 (2013). 

When it comes to adjudicatory procedures, there may be practice guides combined with or in addition to policies. 

How do I find guidance documents?
  • Monitor federal regulations on - You can search/browse documents by date, agency, and topic and set email alerts for particular dockets.
  • Monitor the Federal Register on - You can check search/browse documents by date, agency, and topic and set up email or RSS subscriptions. These subscriptions offer different options: you can receive the daily table of contents for the Register, get updates on particular topics and agencies, or customize a subscription.
  • Be on top of current news sources for the agency/topic you are interested in.
  • Browsing agency websites
  • Read/be aware of changes in secondary sources. Treatises and practice guides are likely to discuss relevant guidance. Supplements, new pages, and new editions come out quite frequently and will likely reference developments in this area.


A few helpful environment-related guidance documents:


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