Federal agencies are the specialized bodies Congress creates to carry out federal law, and the Federal Register currently lists roughly 444 of them.1Federal Register. Agencies They translate broad legislation into enforceable rules, investigate violations, and impose penalties. Their power is substantial. It is not unlimited. Courts, Congress, and the President each constrain what agencies can do, and a run of recent Supreme Court decisions has tightened those constraints in ways that matter.
What a Federal Agency Is
The Administrative Procedure Act defines an “agency” as any authority of the United States government, excluding Congress, the federal courts, and the governments of U.S. territories and the District of Columbia.2Office of the Law Revision Counsel. U.S. Code Title 5 Section 551 – Definitions Each agency traces its existence to an enabling statute: legislation that creates it, spells out its mission, and defines the scope of authority Congress is handing over. Congress delegates this power because it lacks the technical expertise and bandwidth to write every safety standard, pollution limit, or financial disclosure requirement on its own.
The rules agencies produce carry the force of law once finalized. All permanent federal agency rules are compiled in the Code of Federal Regulations, organized across 50 titles covering areas like energy, transportation, labor, and the environment.3GovInfo. Code of Federal Regulations Annual Edition Each title breaks down into chapters (usually named after the issuing agency), then into parts and sections addressing specific topics.
The Main Types of Federal Agencies
Structure matters, because it determines how much direct control the President has over an agency’s decisions and, in turn, how politically insulated the agency can be.
Executive Departments
The 15 cabinet-level departments, including Defense, Treasury, and Health and Human Services, form the backbone of the executive branch. Each is led by a Secretary the President appoints and can remove at will. That removal power gives the administration direct influence over policy direction. Cabinet departments are funded through annual congressional appropriations, giving Congress its own lever.
Independent Regulatory Agencies
Agencies like the Securities and Exchange Commission, the Federal Communications Commission, and the Federal Trade Commission are built to be insulated from day-to-day political pressure. They are typically led by a multi-member board or commission with fixed, staggered terms, so no single president can replace the entire leadership at once. In its 1935 decision in Humphrey’s Executor, the Supreme Court upheld Congress’s power to limit the President’s ability to fire these commissioners, restricting removal to causes like inefficiency or neglect of duty.4Justia U.S. Supreme Court Center. Humphreys Executor v. United States, 295 U.S. 602 (1935)
That protection does not extend to every agency calling itself independent. In 2020, the Supreme Court held that the Consumer Financial Protection Bureau’s structure, a single director shielded from removal, violated the separation of powers. Congress may protect multi-member commissions with for-cause removal restrictions, but concentrating that same insulation in one person goes too far.5Justia U.S. Supreme Court Center. Seila Law LLC v. Consumer Financial Protection Bureau, 591 U.S. (2020) The practical takeaway: independent agencies led by a single director can now generally expect their head to serve at the President’s pleasure.
Government Corporations
A handful of federal entities operate more like businesses, generating revenue through the services they provide while remaining government-owned. The United States Postal Service is the most familiar example, charging for mail delivery and package shipping rather than relying entirely on tax revenue. The Federal Deposit Insurance Corporation, which funds itself through bank-paid premiums, and Amtrak fall into the same category.
How Agencies Make Rules
Rulemaking is the core function that makes agencies powerful. When Congress directs the EPA to regulate air pollution or the FDA to ensure drug safety, the statute rarely spells out every technical requirement. Agencies fill those gaps by writing detailed regulations, and the process is governed by the Administrative Procedure Act.
Notice and Comment
The standard path to a new regulation follows three steps. First, the agency publishes a Notice of Proposed Rulemaking in the Federal Register, laying out the planned rule and the legal authority behind it. Second, the public gets a window, typically 30 to 60 days, to submit written comments, data, and objections. Third, the agency reviews those comments, responds to significant concerns, and publishes the final rule with a statement explaining its reasoning.6Office of the Law Revision Counsel. U.S. Code Title 5 Section 553 – Rule Making
Not every regulation follows this path. The APA allows agencies to skip notice-and-comment for interpretive rules, internal procedural guidance, and situations where the agency finds good cause that public input would be impractical or against the public interest. Those exceptions explain why some rules seem to appear without a comment period.
Cost-Benefit Review for Major Rules
Rules with heavy economic impact face an extra layer of review. Under Executive Order 12866, any proposed regulation expected to have an annual economic effect of $100 million or more is classified as a “significant regulatory action” and must be submitted to the Office of Information and Regulatory Affairs within the Office of Management and Budget.7U.S. EPA. Summary of Executive Order 12866 – Regulatory Planning and Review Agencies must quantify the anticipated costs and benefits as accurately as possible. The review acts as a check on regulations whose costs to businesses or consumers would far outweigh their expected benefits.
Your Right to Petition
You do not have to wait for an agency to act on its own. The APA gives any interested person the right to petition a federal agency to create a new rule, amend an existing one, or repeal a rule entirely.6Office of the Law Revision Counsel. U.S. Code Title 5 Section 553 – Rule Making The agency must respond, though it is not required to grant the request. Most people never use this tool. It exists, and it costs nothing.
Enforcement and In-House Adjudication
Writing rules would mean little if agencies could not enforce them. Federal agencies can conduct investigations, issue administrative subpoenas for documents or testimony, and impose civil monetary penalties on individuals and companies that violate their regulations. The Department of Labor, for example, publishes an annually updated penalty schedule covering violations of wage, safety, and labor laws.8U.S. Department of Labor. Civil Money Penalty Inflation Adjustments These amounts are adjusted every year by January 15 to keep pace with inflation, as required by the Federal Civil Penalties Inflation Adjustment Act.
Agencies also resolve disputes through their own administrative courts, staffed by administrative law judges who hear cases involving the agency’s regulations. Proceedings look like scaled-down federal trials, with evidence, testimony, and written decisions, but they happen inside the agency rather than in front of an Article III judge. Parties who disagree with the outcome can appeal to the federal courts.
Limits on Agency Power
Agency authority is broad, but it runs into hard boundaries set by the courts, Congress, and the Constitution. Those limits have expanded meaningfully in the last few years.
Judicial Review Under the APA
Courts can strike down agency actions they find to be arbitrary, unreasonable, an abuse of discretion, or beyond the authority Congress actually granted.9Office of the Law Revision Counsel. U.S. Code Title 5 Section 706 Courts can also force an agency to act when it has unlawfully sat on a duty Congress assigned to it. This review is the primary mechanism for holding agencies accountable when they overreach or ignore their own procedures.
The End of Chevron Deference
For 40 years, courts applied a doctrine called Chevron deference: when a statute was ambiguous, judges deferred to the agency’s interpretation as long as it was reasonable. That era ended in June 2024. In Loper Bright Enterprises v. Raimondo, the Supreme Court overruled Chevron outright, holding that courts must exercise their own independent judgment when deciding whether an agency has acted within its statutory authority.10Justia U.S. Supreme Court Center. Loper Bright Enterprises v. Raimondo, 603 U.S. (2024) Judges may still look at how an agency reads a statute, but they are no longer required to accept that reading simply because the law is unclear.
This is the single biggest shift in administrative law in decades. Agencies now face a harder road defending regulations in court, because judges will read the statute themselves rather than giving the agency the benefit of the doubt. Challenges that would have failed under Chevron now have a real chance.
The Major Questions Doctrine
Even before Chevron fell, the Supreme Court was narrowing agency power through what it formalized as the major questions doctrine. In West Virginia v. EPA (2022), the Court held that when an agency claims authority to make a rule of vast economic or political significance, it must point to clear congressional authorization rather than a vague or general statutory provision.11Justia U.S. Supreme Court Center. West Virginia v. Environmental Protection Agency, 597 U.S. (2022) The doctrine effectively blocks agencies from using old or broadly worded statutes to justify sweeping new regulatory programs Congress never specifically approved.
Congressional Oversight and the CRA
Congress controls agencies through the budget process, confirmation hearings, and direct oversight investigations. It also has a blunt tool for killing specific rules: the Congressional Review Act. Under the CRA, every final agency rule must be submitted to both chambers of Congress and the Government Accountability Office before it can take effect.12Office of the Law Revision Counsel. U.S. Code Title 5 Section 801 – Congressional Review Congress then has 60 days to pass a joint resolution of disapproval. If that resolution becomes law, the rule is void, and the agency cannot reissue anything substantially similar unless Congress later passes new legislation authorizing it.13U.S. Government Accountability Office. FAQs on the Congressional Review Act Major rules face an additional hurdle: they cannot take effect until at least 60 days after publication, giving Congress time to act.
How the Public Sees In
Federal agencies are not black boxes. Several laws guarantee the public a window into what they are doing.
The Freedom of Information Act
FOIA gives anyone the right to request records from a federal agency, and the agency must respond within 20 working days.14U.S. Department of Justice. The Freedom of Information Act, 5 U.S.C. Section 552 FOIA is one of the most effective tools ordinary people have for holding agencies accountable. Investigative journalists, researchers, and advocacy organizations use it constantly.
Open Meetings
Multi-member agencies (those headed by a board or commission whose members are presidentially appointed and Senate-confirmed) must hold their deliberative meetings open to the public under the Government in the Sunshine Act.15Office of the Law Revision Counsel. U.S. Code Title 5 Section 552b – Open Meetings Agencies can close portions of a meeting for specific reasons, including national security, personal privacy, and active law enforcement investigations, but closing a meeting requires a recorded vote by a majority of members. The default is openness.
The Range of Agency Missions
A few examples show how much ground federal agencies cover. The Environmental Protection Agency administers and enforces laws like the Clean Air Act and the Clean Water Act by setting national pollution standards. Although the word “independent” is sometimes attached to it, the EPA administrator serves at the President’s pleasure, making the agency more politically responsive than a multi-member commission like the SEC.
The Food and Drug Administration, housed within the Department of Health and Human Services, is responsible for the safety and effectiveness of drugs, biological products, medical devices, and the nation’s food supply.16U.S. Food and Drug Administration. What We Do Its authority to block an unsafe product or force a recall gives it outsized influence over industries worth trillions.
The Federal Bureau of Investigation, part of the Department of Justice, works as both a national security organization and a federal law enforcement agency, investigating crimes that cross state lines or involve federal interests. The Social Security Administration, an independent agency, manages retirement, disability, and survivor benefits for tens of millions of Americans. And NASA runs the civilian space program and aerospace research, a reminder that federal agencies handle everything from monthly benefit checks to Mars rovers.