Canons of Construction: How Courts Interpret Statutes

Plain meaning comes first

We have stated time and again that courts must presume that a legislature says in a statute what it means and means in a statute what it says there.

Connecticut Nat’l Bank v. Germain, 503 U.S. 249, 253–54 (1992)

When the words are clear, the Court added, “this first canon is also the last: ‘judicial inquiry is complete.'” The other canons help when the words are unclear.

Reading words in context

• Noscitur a sociis: “a word is known by the company it keeps” (Yates v. United States, 574 U.S. 528, 543 (2015) (plurality opinion)).
• Ejusdem generis: “where general words follow specific words in a statutory enumeration, the general words are [usually] construed to embrace only objects similar in nature to those objects enumerated by the preceding specific words” (Yates, 574 U.S. at 545).
• Expressio unius est exclusio alterius: “expressing one item of [an] associated group or series excludes another left unmentioned” (Chevron U.S.A. Inc. v. Echazabal, 536 U.S. 73, 80 (2002)). However, the Court added that the canon applies only when the items “should be understood to go hand in hand” (at 81).
• In pari materia: laws on the same subject are read together, because “a legislative body generally uses a particular word with a consistent meaning in a given context” (Erlenbaugh v. United States, 409 U.S. 239, 243 (1972)).

Giving every word effect

It is “a cardinal principle of statutory construction” that “a statute ought, upon the whole, to be so construed that, if it can be prevented, no clause, sentence, or word shall be superfluous, void, or insignificant.”

TRW Inc. v. Andrews, 534 U.S. 19, 31 (2001)

Similarly, courts avoid absurd readings: “interpretations of a statute which would produce absurd results are to be avoided if alternative interpretations consistent with the legislative purpose are available” (Griffin v. Oceanic Contractors, Inc., 458 U.S. 564, 575 (1982)).

Lenity and constitutional avoidance

In criminal cases, “ambiguity concerning the ambit of criminal statutes should be resolved in favor of lenity” (United States v. Bass, 404 U.S. 336, 347 (1971)). Under the avoidance canon, the Court “will not pass upon a constitutional question although properly presented by the record, if there is also present some other ground upon which the case may be disposed of” (Ashwander v. TVA, 297 U.S. 288, 347 (1936) (Brandeis, J., concurring)).

Agency interpretations after Loper Bright

Chevron is overruled. Courts must exercise their independent judgment in deciding whether an agency has acted within its statutory authority, as the APA requires.

Loper Bright Enterprises v. Raimondo, 603 U.S. 369, 412 (2024)

For 40 years, courts often deferred to an agency’s reasonable reading of an unclear statute. Now, courts decide the best reading themselves, using the same canons described here.

Researching canons of construction in your state

First, find the statute or rule that governs canons of construction where you live. State law controls most of these questions, so the answer can change from one state to the next. Next, read recent decisions from the appellate courts in your state. They show how judges apply the law today. Also, check the local rules of the court that would hear your case. Our state procedures guide links to each state’s official rules. In addition, the Research Center explains how to confirm a source is still good law.

Sources and further reading

Official sources used on this page:

• tile.loc.gov
• tile.loc.gov
• tile.loc.gov
• tile.loc.gov
• supremecourt.gov

Related reading on Lawtopolis:

• Judicial Canons: The Codes of Conduct Judges Follow
• Contract Interpretation and the Parol Evidence Rule
• The Hierarchy of Law: From Natural Rights to the Constitution, Statutes, Regulations and the UCC