Anyone considering law school will be told “law school does not teach you law, but how to think like a lawyer.” This post seeks to briefly explain what that means exactly in (admittedly) broad strokes. The intended audience of this post is prospective law students, early law students, and the general public, though I hope that even seasoned law students and professionals can read this and gain some insight from making the implicit practices of the profession, explicit.
What is “The Common Law”?
Broadly speaking the world is divided into common law and civil law systems. Common law tends to be prevalent in countries influenced by British traditions. Historically, common law practice evolved in medieval England. In the rest of the world, civil law dominates. Painting with broad strokes and ignoring the idiosyncrasies of history, the dominance of civil law in the rest of the world is also predominantly for historical reasons. Civil law nations tend to be influenced by the Napoleonic Code, which itself was influenced by the rediscovery of Roman law.
When most people think about law school, they probably think of something along the lines of memorizing a gigantic rule book and applying those rules to various situations. That is essentially what occurs in a civil law system. Civil law systems are predominantly statutory. A statute is a rule that the legislature passes, and tend to work as codified systems (this is a slight simplification).
However, the United States is a common law country. Common law, also known as judge-made law, is law that does not come from codified statutes but rather from judicial decisions. There are typically three levels of courts: trial, appellate, and a court of last resort (the federal court system is structured this way; states with parallel court systems also tend to follow this pattern, though the names of the state courts can be different). Generally speaking, parties first bring their dispute to a trial court, where the court determines the facts of the case and applies the law to the facts to decide which party should win. The parties may then appeal the decision to the appellate court, which then examines if the trial court applied the law correctly. Some appellate decisions are then appealed to the court of last resort. Common law are the rules contained in the decisions of all courts. American law schools tend to focus on reading appellate decisions (decisions coming out of the appellate courts and court of last resort) in order to derive the common law. “Think like a lawyer” is actually shorthand for think like a common law-lawyer.
This explanation is actually overly simplified in two major ways. The first is that, as any high school civics class will teach you, legislatures like Congress also create laws through its own processes of proposing bills, passing them through the houses, and presenting it to the executive to sign or to veto. Laws passed through legislative processes in the US are statutes which interact with the common law in complex ways. Almost universally, courts accept that statutory law trumps common law if the two conflict, but there is remarkable disagreement over what counts as conflict (and also, if the legislation was adopted with the assumption that the background common law was being left alone or intended to replace the common law). In fact, some argue that American law is moving away from common law towards a more codified statutory system like civil law countries (others argue that if this is not happening, it should be happening).
The second major simplification is how lawyers derive the common law from judicial decisions. The process of working out the common law and its applications is the crux of law school. Saying that common law is just reading decisions and applying its rules, blurs the craft and is like saying that computer programming is “just coding” or that plumbing is just “fixing pipes”. Common law reasoning, similar to programming and plumbing comes with its own professional norms, heritage, and tools. The rest of this article explains the mechanics and underlying theory of common law reasoning.
Reading Cases: A Primer
An appellate decision generally has a facts section which describes the factual findings of the case, determined at trial, and an application of the law to reach a final decision the case. Lawyers call the result, along with the rationale to reach such a result, the holding. The rest of the court’s decision is dicta. In theory, common law comes from the holding of the cases. Here lies the rub — reasonable lawyers disagree over what “counts” as the holding or the dicta. A court will rarely ever declare explicitly what the rule is. Even if the court does, since all decisions come from a real life controversy, there can be reasonable disagreement over the rationale or even existence of elements of the holding. There are of course parts of a case that people agree should not be part of the holding, for example, the names of the parties or clearly irrelevant details. But reasonable parties can disagree on the facts that are necessary to the decision and those that are not. Common law, to a degree, assumes that people can read the rules out of individual decisions to construct a system of rules and laws to govern.
In law school, professors explore this by the “Socratic method,” which is essentially a series of questions forcing students to articulate the rule, examine the basis for their reasoning, and recognize the ambiguities in the rule. For a classic example, consider a case where Mr. Henry, an elderly man who once designed a park, visits that park frequently in his motorized wheelchair. One day, he gets barred from entering the park by police, who cite a local law “No Vehicles in the Park”. If Mr. Henry litigates the case, perhaps the court will say “Obviously, Mr. Henry, an elderly architect, can be in the park with his motorized wheelchair, because the law is meant to preserve the peace and quiet by keeping out loud vehicles”. The result is clear — Mr. Henry can visit the park in his motorized wheelchair (part of the holding). The fact that his name is Mr. Henry and that he is an architect seem clearly unnecessary to the result (obviously dicta). One can imagine that if the same case came up, only now with a Mrs. Smith who is a retired nurse instead of Mr. Henry who is a retired architect, the case would have the same result. But the rest is deceptively ambiguous. Is the fact that Mr. Henry is elderly part of the rationale for how the case turned out or not? What if teenagers come into the park to race on motorized wheelchairs — is that not banned under “No Vehicles in the Park”? Is keeping the peace and quiet the limit of the rule or just one of the purposes of the rule? The Socratic method is meant (among other things, like to humiliate the pants off of you) to help the student recognize the latent ambiguities and complexities of decisions.
Putting it All Together
The common law however is not just individual cases but the structure these cases create. Learning to understand and draw the rule out of cases is the first step to fitting these cases together. Law school explores the structuring of common law through the “casebook method”. The aspiration of the casebook method is that after reading many cases, a lawyer figures out the rules as they are fleshed out, case-by-case. Returning to the example above, perhaps a case will find that motorized wheelchairs are allowed, but later cases find that motorcycles, and bicycles are not. It stands to reason that tricycles and ATVs are not allowed either. Perhaps one way to stitch the cases together is to say that the law bans purely recreational vehicles, but not the “necessary” vehicles. Conversely, perhaps the principle is not recreational v. necessary, but rather, two-wheeled v. non- two-wheeled vehicle. A case that either explicitly says the law bans recreational vehicles, or a case that bans tricycles might foreclose the latter interpretation (implicitly, as tricycles would not fit the number of wheels theory). In theory, the cases form a structure together and over time, and this structure is the common law.
The Genius/Headache of the Common Law
The law student learns quickly that cases don’t fit together neatly. On top of the challenge of drawing different holdings out of the same case, cases are frequently contradictory, “wrong,” ambiguous, or leave gaps in the law. Recall how common law is “made” by the individual decisions of judges. This leads to all sorts of oddities from a practical point of view. Judges separated by time, space, and ideology may disagree on the right result or reasoning for cases, leading to contradictory decisions. Issues that are obvious are not litigated since litigation is costly and no one wants to waste money paying lawyers for a clearly losing position, leading to gaps in the law (sometimes what is widely accepted as “obvious” and thus not litigated turns out not to be so obvious if ever litigated). Sometimes cases read together make no sense, because judges disagree with each other, or even their earlier selves. Sometimes a judge may not give the “real” reasons for a decision, hiding the rationale under formalist logic and language (the admirers of the legal philosophy “legal realism” believe that this is the case in the vast majority, if not all, cases). Decisions may be poorly written, or argue from such abstract principles that they offer no substantive guidance. Returning to the example, cases in different states looking at the exact same rule could come out with different results on the impermissibility of tricycles in the park. A court may change its mind over time after seeing so many crying toddlers, or perhaps tricycle cases are never even brought to court.
The universe of cases that are relevant is another loose joint in common law. Both case-law and legislative statutes are sprawling. Laws read broadly can conflict with one another. For example, the legislature may pass a law that protects bikers in public spaces. If this law and the law that there are “No Vehicles in the Park” are read broadly, they would contradict. One way to solve this contradiction would be to read one law more narrowly than the other. The former rule can, perhaps, be read narrowly so that “protect” means to physically protect bikers from cars but not to protect the bikers’ right of way. Alternatively, the latter rule can be read narrowly so that a bike does not come within the scope of a “vehicle” at all. Another way to solve the contradiction is to find that one law binds the other because one law is superior or might already have a crave-out for another “No Vehicle in the Park, except for bikes”. An even easier way to resolve the issue would be for the judge to just ignore it. But even if lawyers and judges make an honest effort to address the relevant case-law, reasonable people can disagree on the scope of the reasonable law (for example, is biking a form of expression implicating the 1st amendment? Is the act of taking away the right to bike through a park equivalent to taking someone’s liberty and therefore implicates due process? etc).
The Common Law’s Answer
The common law method ignores these realities and instead relies on several legal fictions. A legal fiction is essentially admitting a certain reality but then acting as if another reality is true. One of the common law’s legal fictions is that law comes from pronouncements of “the court” and not individuals. Cases would never say that “the decision in the precedent case was decided that way because the judge in that case was a well known liberal. Since we don’t like liberals, we come to the opposite conclusion in the present case.” Instead, a decision would attack the logic of a prior case or distinguish itself from that case, if the court wanted a different result. Conversely, a court will agree with the rationale or analogize to a prior case if it wants the same result. Of course, as a practical matter, advocates try to divine what the judge will decide by reading their earlier opinions, and as a practical matter no one wants to be seen as inconsistent with themselves. However, these practicalities are not treated as part of “the law”.
A corollary of this legal fiction is that the cases “fit” together in some way, and the law is not just a collection of decisions made by some people, in some place, at some time. There is some animating principle behind the madness that can be understood. Common lawyering is discovering this principle and articulating it. For example, with a collection of decisions on what is or is not allowed in the park, a principle may emerge that fits most, if not all, of the cases. A good common law judge or lawyer recognizes this principle and expresses it explicitly. The principle is unlikely to fit all the cases, and the good common law judge has to explain why; for example, some cases may appear inconsistent but are actually consistent, are an exception to the general principle, or in extreme situations, were decided incorrectly in light of the principle. Dworkin, one of the most important teachers of the common law, likened common law to a great chain novel, where each author adds another link by fitting earlier links with the best justification.
There is much philosophical debate over if the law has a “right answer.” Some argue that read correctly, the common law produces one correct answer to legal question. Others argue that the common law can be read fairly to give a multitude of answers, if not any answer. This is a philosophical topic that much ink has been spilt over, and won’t be tackled here.
The Common Law as “the general bank and capital of nations and ages”
In addition to historical reasons, there are good policy reasons to have the Gordian knot that is common law. The reasons that to support the common law are similar to Burke’s defenses of tradition. One of the core principles of common law is stare decisis (let it stand), a certain respect for precedent. Instead of reasoning from first principles every time a controversy arises, a court should look for the decisions of courts before it for guidance, creating stability/predictability and utilizing the wisdom of the past. However, courts can overrule precedent if it is clearly wrong either, explicitly, or implicitly by creating exceptions and distinctions (Brown v. Board of Education for example, never overruled Plessy v. Ferguson explicitly but has done so de facto). Many have characterized the common law as judicial wisdom accumulated over time, informed by experience and the wisdom of generations. Judges reflecting on the consequences of an initial rule can change the rule in light of that experience.
The Common Law and Flexibility
Supporters of the common law see its flexibility not as a defect, but as part of the design. In addition to the age-old adage that there should be exceptions to rules, common law might be messy because, frankly, life is messy.
The flexibility of the common law allows it to grow, intentionally and unintentionally. Not uncommonly, judges who think they are simply summarizing the law, or describing existing law can accidentally create new law (this probably happened in both Chevon v. Natural Resource Defense Council, Inc. and Penn Central Transportation Company v. New York City, both pivotal cases in Supreme Court jurisprudence). Sometimes it is purposeful, re-characterizing old cases to derive a new principle, or leaving breadcrumbs in seemingly unrelated cases in order to draw on in later cases.
Yet another defense of the common law, proponents would argue, is to challenge the idea that the common law is “flexible” at all. Those proponents would argue that most of the law is actually consistent and well-settled; it only appears contradictory because we focus on the minority of cases where clashes exist.
A final argument in favor of the common law, and perhaps the most realistic one, is that the common law is part of our heritage. Whatever strengths and weaknesses the common law has, thinking like a lawyer means joining this tradition, for the better or for the worse.
This piece benefited immensely from the suggestions of several patient readers including Tom Ludwig, Yvan Scher, Tom Snyder, and Nastassia Shcherbatsevich. All errors are my own.