Fact check: Does the U.S. Code or federal statutes use the term "illegal alien" or "alien" and in which sections?

1. How the Code Labels People—Plain Evidence from Key Sections that Matter

A close read of seminal criminal and immigration provisions shows the U.S. Code relies on “alien” as the operative term to describe non‑citizens in conduct statutes governing entry, smuggling, and harboring. For example, 8 U.S.C. § 1325 addresses “improper entry by alien,” setting out penalties for an alien who enters or attempts to enter the United States at a time or place other than as designated by immigration officers ^[1]. Similarly, 8 U.S.C. § 1324 uses “alien” to define the class of persons whom the statute prohibits bringing into or harboring in the United States; these sections treat “alien” as the legal descriptor for non‑citizens in the context of criminal enforcement ^{[4] [2]}.

2. The Phrase “Illegal Alien”—Rare, Specific, and Not Uniformly Defined

Scholars and legal summaries observe that “illegal alien” appears only in a limited number of statutory texts and often in narrow or historic contexts rather than as a general definitional term applied across immigration law. Analytical summaries point out that where “illegal alien” is used, it is not typically accompanied by a single, consistent statutory definition that would encompass all non‑citizens lacking authorization; instead, the law frames unauthorized presence or entry through conduct‑based provisions that reference “alien” and specify the unlawful acts ^[3]. A 2018 discussion explicitly notes the scarcity of the phrase in federal law and cautions against treating it as a comprehensive legal category ^[3].

3. What “Alien” Actually Means in Legal Practice and Why Definitions Matter

Legal references and explanatory treatments define “alien” in statutory and administrative contexts as a person who is not a citizen or national of the United States, with the precise contours of status determined by other provisions governing admission, visas, and removability. Interpretive commentary emphasizes that differences in terminology across statutes reflect functional distinctions—such as admission status, entry method, or criminal conduct—rather than synonyms for moral or political labels ^[5]. Because Congress and agencies use “alien” extensively while reserving “illegal alien” for select instances, legal practice evaluates status by reference to specific statutory elements and procedural rules, not by a single epithet.

4. Competing Views and Why Language Choice Sparks Debate

Observers from different perspectives frame the choice between “alien” and “illegal alien” as carrying legal precision or political value: proponents of plain statutory language point to consistent use of “alien” in enforcement statutes as evidence that law aims for neutral categorization, while critics argue that sporadic use of “illegal alien” in some texts and public discourse imports stigmatizing connotations that are not codified uniformly ^{[3] [5]}. Analyses also flag that some statutes historically retained phrases now uncommon in practice, and that administrative guidance and court decisions often interpret “alien” in context to determine legal status and consequences, underscoring how statutory wording interfaces with enforcement priorities ^[4].

5. Practical Consequences—Enforcement, Interpretation, and Communication

The predominance of “alien” across core statutory provisions means that courts, prosecutors, and agencies assess immigration offenses by applying statutory elements tied to conduct—entry, harboring, employment—rather than by relying on a single label. Where “illegal alien” occurs, its limited statutory presence creates potential ambiguity when lawmakers or officials adopt the phrase in policy or rhetoric, prompting litigation and interpretive disputes about whether the term carries unique legal weight ^{[1] [2]}. This legal landscape explains why authoritative resources and legal commentators emphasize precise statutory citations and definitions when discussing immigration status and enforcement, and why terminological choices can signal different policy or advocacy agendas ^{[3] [5]}.