Legal Analysis Topic 2: Law Can be Like Science

Dear Student,

Welcome to The Law School Playbook!  I’m Halle Hara, a professor of academic success and personal skills coach to law students and attorneys.  I’m glad you’re here!  The topic we are addressing today is inductive reasoning, another well-known type of reasoning often used in law school and in practice.  While you are more likely to see rule-based reasoning on law school exams (particularly during your first year), my guess is that you’ve talked about inductive reasoning in your legal writing course (even if your professor hasn’t referred to it as such).

Unlike deductive reasoning (the type of reasoning used in math), inductive reasoning does not produce a certain conclusion.  This is the type of reasoning used in science—as Professor Barbara Kalinowski has explained:

A scientist conducts enough trials of an experiment to be able to observe a pattern in the results. Numerous similar results can then suggest a general hypothesis: if A, B, and C all have result X, then D (which is similar to A, B, and C) will probably also have result X.  As long as the scientist conducts enough trials, he or she can have confidence in the accuracy of the hypothesis.  It is unlikely, however, that a scientist would suggest that simply repeating results consistently creates scientific proof or absolute certainty in the result. The process of induction as applied to legal reasoning is no different.

There are many types of inductive reasoning, but we will focus on two:  (1) inductive generalization and (2) reasoning by analogy (also known as analogical reasoning).

First we will address inductive generalization.  Inductive generalization is used when there is exists no enacted law for a particular principle.  As we know, however, common law rules often emerge from a series of opinions over time.  These decisions lead to a generally accepted and reliable rule, even though that rule has not been enacted.  Thus, common law rules are an example of inductive generalization.

Let’s look at an example cited by as Professor Kalinowski.  She refers to Justice Cardozo’s opinion in MacPherson v. Buick Motor Co., a products liability case that involved an injury from a collapsed wooden wheel of an automobile.  In that case, Justice Cardozo used inductive reasoning to create a rule that allowed the injured owner to collect damages from the manufacturer.  Professor Kalinowski explains:

Cardozo compared the results of sixteen factually diverse products liability cases.  He identified relevant similar or divergent features between the cases, such as whether the defendant was a manufacturer and whether there was a near certainty of injury, should the product be defective. By analyzing a large enough number of specific circumstances of liability and comparing relevant resemblances between them, Cardozo was able to derive a new (and yet, not new) principle:  A manufacturer who constructs an automobile using defective component parts may be liable to a remote purchaser of the automobile for injuries resulting from those parts.

Thus, Professor Kalinowski concludes that “Cardozo used enough relevant particulars to generalize a reliable statement of the law.”

It is important to note that we also engage in this type of inductive generalization in our everyday lives, even before we come to law school.  More specifically, we engage in case synthesis to construct a rule that can be used to predict an outcome.  My high-school-aged son, for example, recently engaged in synthesis to determine if his conduct would be acceptable to my next door neighbor.

Let’s look at that example.  We have a neighbor who isn’t particularly fond of my son playing basketball while he listens to music in our backyard.  One day, my son was attempting a trick shot when his ball went over the fence and nearly hit my neighbor’s greenhouse.  My neighbor came over moments later, carrying the basketball, and gave my son an earful about the damage he could have caused.  Just a few days later, my son managed to keep the ball in our yard, but our neighbor complained to him that his rap music (which was at an 8 out of 10 on our portable speaker) was disturbing her, and she demanded that he turn it down.  On a third day, my son was listening to the Minecraft soundtrack (which is instrumental music—also at an 8 out of 10 on our portable speaker) when his basketball when into our neighbor’s yard at the far end of her property.  Luckily, it was nowhere near the greenhouse, and my son walked around the fence (instead of climbing over it) to retrieve it.  He was startled when he saw the neighbor weeding in her backyard.  She greeted him with a friendly “hello” and said, “I’m glad you went around instead of over the fence.  You could hurt yourself by doing that.”  As my son turned to leave, my neighbor said, “and, by the way, this music is lovely.”  My son thanked her and went on his way.  After those three encounters, another high school boy came over to play basketball with my son.  He said, “I heard your neighbor is kinda mean.  Should we play at the school instead of here so she doesn’t yell at us?”  My son, having synthesized the three incidents with my neighbor replied, “No.  We should be fine as long as we keep the ball away from her greenhouse, don’t play rap music, and go around instead of climb over the fence.”  Thus, my son used each of the interactions with my neighbor to create a single rule for acceptable conduct (according to my neighbor) while he is playing basketball in our backyard.

My son engaged in the type of thinking that some regard as thinking like a lawyer:  he used the past outcomes to predict appropriate conduct for the present and future, creating a rule when there was none.  By using the past to predict the future we become akin to fortune tellers, not unlike the soothsayer who warned Julius Caesar to “Beware the Ides of March.”  And predicting an outcome doesn’t always pertain to litigation—there are many lawyers who make a living advising companies on, for example, employment law matters or regulatory compliance.

We also use the second type of inductive reasoning—reasoning by analogy—in our everyday lives.  While inductive generalization takes a broad view in comparing authority, reasoning by analogy reasoning takes a narrow view by comparing the facts found in authority.  The general idea is this:  the facts in the prior case are like the facts of this case, so that the rule from the prior case should apply here.  In the most basic terms, analogical reasoning involves finding similarities to predict (or advocate for) a particular outcome.

Turning back to my teenage son, he might argue that he should be allowed to stay out until midnight because his friend is allowed to stay out until midnight.  He might point out that his friend is responsible, stays in touch with his mom, and is never a moment late.  My son might argue that because he is also responsible, stays in touch with me, and is never late, the same curfew should apply to him.  Unlike deductive reasoning, analogical reasoning (much to my son’s dismay) is less certain to result in a particular outcome.

What makes legal analogies even more persuasive than the everyday example involving my son, is that they are rooted in stare decisis.  Thus, analogical reasoning asserts that if key facts found in binding precedent and key facts in a current case are similar, and the legal issues addressed in both are the same, then the court should rule the same or risk failing to adhere to stare decisis.  In the example with my son, I am not bound to follow the decision of another parent.  The trial court is, however, bound by stare decisis to follow a binding court of appeals’ decision if it is sufficiently analogous.

But what does sufficiently analogous mean?  The strength of an analogy is based on the following:

(1)  jurisdiction – we ask:  is the precedent binding?
(2)  legal issues –  we ask:  was the issue before the court the same as the one in this case?
(3)  key facts – we ask:  are the key facts the same or substantially similar to warrant the same outcome?

As you can imagine, because it does not produce a certain outcome, analogical reasoning leaves room for argument on both sides.  In fact, it is not unusual for opposing sides to analogize to the same precedent to persuade the court to rule in its favor.

There are some common mistakes that law students make when using analogical reasoning.  For instance:

  • Law students sometimes point to the outcome in the precedent case as the desired outcome in the current case but fail to include legal analysis.

  • Another common mistake is relying on non-critical facts in the precedent case to suggest an outcome in the current case.

  • Students also sometimes use the key facts, but they fail to explain why those facts are relevant to the conclusion they desire in the current case.

Professor David Romantz and Professor Kathleen E. Vinson created a four-part process for analogical reasoning in their book Legal Analysis: The Fundamental Skill.  The process involves:

Step 1:  using a topic sentence to orient the reader to the law and how it applies.

Step 2:  engaging in a fact-to-fact comparison using only key facts.  The goal here is to include all of the legally significant facts and none of the irrelevant facts.

Step 3:  explaining the reasoning in the precedent case, and how the similar facts in the current case are likely to result the same outcome as the precedent case.  Significantly, the facts used from the precedent case must have been included in the court’s reasoning to reach the outcome.  In essence, you are making sure that you have identified the correct facts in step 2 and explaining to the court why they matter.

Step 4:  reminding the court of the conclusion in a sentence.

It is worth noting that distinguishing a case is the opposite of what we are doing when we engage in analogical reasoning.  More specifically, when we distinguish a case, we are explaining to the court that the facts of the precedent case are different from the current case and therefore lead to a different conclusion.

Many cases involve lawyers or judges using a combination of both deductive reasoning and inductive reasoning.  For example, an attorney might use deductive reasoning to set forth a clear rule and then show how that clear rule was applied in cases with similar facts by using analogical reasoning.  Alternatively, if an attorney is uncertain if a particular rule is clear, that attorney might use both strategies to persuade the court to rule in the client’s favor.  Experience will increase your confidence in determining whether to use deductive reasoning, inductive reasoning, or both.  A good way to practice is to identify the strategies used by the court in the opinions you read for class.  As an added benefit, you’ll be a more engaged reader!

Thanks for listening.  If would you like to read this episode, get suggestions for further reading, or to request individual coaching with me, please visit my website at www.lawschoolplaybook.com.

As always, do your best, and I’ll be rooting for you!

References and Further Reading

Steven J. Burton, An Introduction to Law and Legal Reasoning 25–41, 59–78 (3d ed. 2007).

Charles R. Calleros, Legal Method and Legal Writing 146–51 (7th ed. 2014).

Bradley J. Charles, Applying Law 61–68 (2011).

Christine Coughlin, et al., A Lawyer Writes: A Practical Guide to Legal Analysis 135–62 (2d ed. 2013).

E. Scott Fruehwald, Think Like a Lawyer:  Legal Reasoning for Law Students and Business Professionals (2013).

Barbara Anne Kalinowski, Logic Ab Initio, A Functional Approach to Improving Law Students' Critical Thinking Skills, 22 Legal Writing 109 (2018).

Herbert N. Ramy, Succeeding in Law School 113 (2d ed. 2010).

David Romantz & Kathleen E. Vinson, Legal Analysis: The Fundamental Skill, 50–55 (2d ed. 2009).

Emily Sherwin, A Defense of Analogical Reasoning in Law, Cornell Law Faculty Publications (1999). http://scholarship.law.cornell.edu/facpub/840.

Peter Nash Swisher, Teaching Legal Reasoning in Law School, 74 L. Lib. J. 534 (1981).

The Writing Center at GULC by Maureen Aidasani & Osamudia Guobadia, What Do You Mean “There’s More than One Way to Do It”?  Selecting Methods of Legal Analysis That Work Best, 2004.  https://www.law.georgetown.edu/wp-content/uploads/2018/02/legalanalysismethods.pdf.

Kenneth J. Vandevelde, Thinking Like a Lawyer:  An Introduction to Legal Reasoning 115–30 (2d ed. 2011).