Common Law
“Common law” is among the most treacherous terms in legal argument, because it does not name one thing. It names at least seven, and they are not interchangeable. An argument that is true under one sense can be false under another, so an analysis that lets the term drift mid-stream can look coherent while resting on a moving target. Pinning the sense is therefore the first move whenever a claim turns on “the common law” — the same disambiguation discipline the law merchant requires.
The seven senses
1. Common law vs. statute (judge-made vs. legislated). Law declared by courts in deciding cases, as opposed to law enacted by a legislature. This is the axis on which “the common law” contrasts with positive law in its statutory sense.
2. Common law vs. equity (“Suits at common law”). The “law” side of the historical division between courts of law and courts of equity. This is the sense the Seventh Amendment uses (“Suits at common law”), and it is load-bearing in the public-rights doctrine: whether a claim is “analogous to a common-law action” determines whether a jury-trial right attaches. Here “common law” is doing technical doctrinal work and means something quite specific — not tradition, not natural law.
3. Common law vs. civil, merchant, or admiralty law (the tradition). The Anglo-American adversarial tradition, contrasted with the Continental civil-law tradition, the law merchant, or admiralty. This is the sense the four-lens method’s Legal Tradition lens tests.
4. The English common law as a historical body. The specific corpus of medieval-and-later English judge-made doctrine — what people mean in statements like “imprisonment for debt was unknown to the common law.” This is a claim about what a particular legal system did or did not contain at a particular time, and it is checkable as history.
5. Common law as a customary or natural-law ideal. A pre-statutory law of natural rights, often grounded in custom, reason, or Scripture — Coke’s “artificial reason,” Blackstone’s framing, the “common law founded on the Bible” tradition. This sense is a real intellectual current, but it is aspirational and jurisprudential. The recurring movement error is to treat it as an operative body a litigant can invoke to override enacted law. (See also natural and unnatural order.)
6. General federal common law. Judge-made federal substantive law, the regime of Swift v. Tyson — abolished by Erie in 1938. After Erie there is no general federal common law; federal courts apply state law in diversity. A claim that invokes “federal common law” as a live general source is usually working from the pre-Erie world.
7. The whole body of judicial precedent — “law you can’t find in the statute book.” Common law as a form of law: the accumulated decisions in the case reporters, binding through stare decisis, that you locate by legal research rather than by reading any legislative record. This is the sense behind a common and partly-justified movement complaint — that the operative law is not in the statutes a citizen can read, but in thousands of cases accessible only through training. The observation has a true core (case law is judge-made and lives in the reporters, not the code) and an overreach (that it is therefore hidden or off-the-record). It is not concealed: precedent is published, indexed, citable, and public. It is “hidden” only in being voluminous and requiring expertise — which is a real knowledge-asymmetry problem, not a secret body of law. Distinguish “not in the legislative record” (true) from “unavailable” or “secret” (false).
Why the distinctions matter
The senses are not academic. The dangerous moves are the slides between them:
- Between §4 and §5 — treating the romantic natural-law ideal (§5) as if it were the historical English body (§4), so that an aspirational “the common law protects X” is asserted as settled doctrine.
- Between §2 and §3 — reading the technical “Suits at common law” (§2, law-vs-equity, jury-trial-attaching) as though it meant the broad tradition (§3), which inflates a narrow procedural test into a sweeping claim about which system governs.
- Between §7 and §1 — moving from “the operative law is judge-made precedent not in the statute book” (§7, largely true) to “therefore the statutory law is not the real law” (an overreach §1 does not support).
When this site evaluates a claim resting on “the common law,” it should name which sense is in play and hold it fixed. Where the movement’s argument depends on the term shifting — most often from §5 or §7 into §1 or §4 — that shift is usually where the argument fails, and identifying it is the analytical work.