In federal law, “arbitrary and capricious” means an agency decision that lacks a rational basis — one that ignores relevant evidence, departs from accepted legal principles, or cannot be traced to sound reasoning. It is the standard courts use under the Administrative Procedure Act to decide whether to strike down a government agency’s action. The two words do slightly different work: “arbitrary” points to a decision made without a reasoned foundation, and “capricious” points to one that is impulsive or unexplained. Courts pair them because they capture different flavors of the same defect.
The phrase carries more weight than everyday English suggests. A decision is not arbitrary just because someone disagrees with it, or because a judge would have chosen differently. The standard asks a narrower question. Did the agency look at what it was supposed to look at, and does its explanation hold together? If yes, the decision stands.
The Four Ways an Agency Fails the Test
The Supreme Court gave the standard its working shape in Motor Vehicle Manufacturers Ass’n v. State Farm Mutual Automobile Insurance Co. (1983). That case identified four specific reasons a court will set an agency action aside:
- The agency relied on factors Congress never intended it to consider.
- The agency entirely failed to address an important aspect of the problem before it.
- The agency’s explanation runs counter to the evidence in the record it compiled.
- The conclusion is so implausible it cannot be chalked up to a reasonable difference in view or to agency expertise.
Those four factors are the workhorse of administrative law. Nearly every challenge to a federal rule invokes at least one of them. The Court also said the agency must “articulate a satisfactory explanation for its action” and draw a “rational connection between the facts found and the choice made.”1Justia U.S. Supreme Court Center. Motor Vehicle Mfrs. Ass’n v. State Farm Mutual Automobile Ins. Co. This is sometimes called the “hard look” doctrine: the agency must take a hard look at the problem before deciding, and the court takes a hard look at what the agency did.
Where the Standard Comes From
The arbitrary and capricious standard sits in Section 706 of the Administrative Procedure Act. Under 5 U.S.C. § 706(2)(A), a reviewing court must “hold unlawful and set aside agency action, findings, and conclusions” found to be “arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law.”2Office of the Law Revision Counsel. 5 USC 706 – Scope of Review
Section 706 lists other grounds too — constitutional violations, actions exceeding statutory authority, and failure to follow required procedures. The arbitrary and capricious ground is the broadest and the most commonly invoked. It governs informal rulemaking, which is how most federal regulations get made.
How Courts Actually Review the Decision
The scope of review is officially “narrow.” Courts are not supposed to substitute their own judgment for the agency’s. In practice, the standard has real bite. The foundational case Citizens to Preserve Overton Park v. Volpe (1971) established that a court must decide whether the agency considered the relevant factors and whether it made a clear error of judgment. That inquiry can get searching.
The review is backward-looking. Courts examine “the whole record or those parts of it cited by a party,”2Office of the Law Revision Counsel. 5 USC 706 – Scope of Review meaning the evidence that was in front of the agency at the time, not new evidence produced later. Courts also reject “post hoc rationalizations” — explanations invented by agency lawyers during litigation that were not part of the original decision.
The challenger carries the burden. Agencies benefit from what courts call a “presumption of regularity,” meaning officials are presumed to have discharged their duties lawfully until someone shows otherwise with meaningful evidence.
What the Standard Looks Like in Real Cases
Some of the highest-profile government disputes of the past decade turned on arbitrary and capricious review.
The DACA Rescission
In DHS v. Regents of the University of California (2020), the Supreme Court held that the Department of Homeland Security’s attempt to end the Deferred Action for Childhood Arrivals program was arbitrary and capricious. Two failures mattered. DHS treated its conclusion that DACA’s benefits might be illegal as reason to also end the program’s separate forbearance policy, without analyzing whether forbearance could survive on its own. And DHS ignored the reliance interests of hundreds of thousands of people who had arranged their lives around the program. The Court tied this to the classic State Farm error: failing to consider an important aspect of the problem.3Supreme Court of the United States. Department of Homeland Security v. Regents of the University of California
The Census Citizenship Question
In Department of Commerce v. New York (2019), the Court blocked the addition of a citizenship question to the 2020 Census. Chief Justice Roberts, writing for the majority, concluded that the stated justification — enforcing the Voting Rights Act — “cannot adequately be explained” given the administrative record. The explanation was contrived, a rationale that did not match the actual decisionmaking process. The matter was sent back to the agency.
State Farm Itself
The case that built the framework involved seatbelts. The National Highway Traffic Safety Administration rescinded a rule requiring passive restraints (automatic seatbelts or airbags) in new cars. The Court found the rescission arbitrary because the agency failed to consider an obvious alternative: requiring airbags instead of scrapping the entire rule. The analysis was incomplete, and the Court sent it back for a proper explanation.1Justia U.S. Supreme Court Center. Motor Vehicle Mfrs. Ass’n v. State Farm Mutual Automobile Ins. Co.
When an Agency Changes Its Mind
Agencies are allowed to change policies. In FCC v. Fox Television Stations (2009), the Supreme Court confirmed that a reversal does not automatically trigger heightened scrutiny; the ordinary arbitrary and capricious test applies. But reversals carry a catch. The agency must acknowledge it is changing position and show there are good reasons for the new policy.
When a reversal upsets longstanding expectations, the stakes rise. The Court in DACA said an agency changing course must “be cognizant that longstanding policies may have engendered serious reliance interests that must be taken into account.”3Supreme Court of the United States. Department of Homeland Security v. Regents of the University of California An agency that points to a new legal interpretation without addressing who relied on the old rule, and how, is likely to lose.
Beyond Government Agencies: ERISA Benefit Denials
The standard reaches past administrative law. It also governs disputes under the Employee Retirement Income Security Act. When an ERISA plan gives its administrator discretion to interpret the plan and decide claims, courts review those decisions under an abuse-of-discretion test that closely tracks arbitrary and capricious analysis.
This matters most when a health insurer or pension fund denies a claim. If the plan document grants the administrator discretionary authority, you cannot simply argue the denial was wrong. You have to show the decision had no rational basis, read the plan contrary to its own terms, or was made without considering the relevant evidence. The decision does not need to be the one a court would have reached. It just needs to be grounded in reason. Courts look at whether the plan was interpreted consistently, whether the reading was fair on its face, and whether the decision furthered the plan’s purposes.
What the Standard Does Not Mean
A few misconceptions are worth clearing up. A decision is not arbitrary and capricious simply because a court would have decided differently. The standard asks whether the agency’s reasoning was rational, not whether it was optimal. Courts give agencies room to exercise judgment inside their areas of expertise.
Conflicting evidence in the record does not automatically doom a decision. Agencies routinely face dueling expert reports, opposing public comments, and competing data. The question is whether the agency acknowledged the conflict and explained why it credited some information over the rest. Ignoring contrary evidence is a problem. Addressing it and explaining the choice is not.
Minor procedural errors do not sink an otherwise well-reasoned action either. The APA requires courts to account for “prejudicial error,” meaning a mistake only matters if it affected the outcome. Harmless slips do not undo the decision.
What Happens When the Challenger Wins
Winning an arbitrary and capricious challenge usually does not deliver the outcome the challenger wanted. The standard remedy is vacatur: the court strikes down the agency’s action and sends it back for the agency to try again with a proper explanation. The agency gets another shot at the same result, so long as it does the analytical work this time.4Administrative Conference of the United States. The Unusual Remedy of Remand Without Vacatur
In some cases, courts use a softer tool called “remand without vacatur,” where the rule stays in effect while the agency fixes its reasoning. Courts choose this path when vacating the rule would cause serious disruption, such as leaving an entire industry without a regulatory framework while the agency redoes its homework.4Administrative Conference of the United States. The Unusual Remedy of Remand Without Vacatur
Courts almost never order an agency to adopt a specific policy. The judicial role is to police the reasoning process, not to make the substantive choice. If the agency can offer a well-reasoned explanation for the same outcome on remand, that outcome will survive review.