Unmasking Logical Fallacies: A Guide for Recognizing and Avoiding Common Pitfalls
By: Joshua Lucas Rojas*
A lawyer’s ability to persuade is fundamental to effective advocacy. Unfortunately, amid the complexity of legal discourse, logical fallacies can arise, undermining the credibility of arguments.[1] Logic, the cornerstone of rational thought, guides reasoned judgment.[2] Conversely, a logical fallacy represents flawed reasoning disguised as valid.[3] These fallacies pervade legal discourse and often evade detection.[4] Although, on occasion, due to “the demands of justice,” lawyers may utilize logical fallacies in non-fallacious ways, “[b]ecause fallacies lead one astray, it is important to . . . avoid[] them” whenever possible.[5]
This blog highlights two common logical fallacies in legal discourse: (1) Argumentum Ad Hominem[6] and (2) Ignoratio Elenchi[7].[8] By examining these fallacies, legal practitioners can sharpen their analytical skills, refine their argumentative techniques, and ultimately enhance their ability to construct cogent and compelling legal arguments. Understanding and identifying fallacies fortifies one’s ability to advocate and fosters a critical lens through which to evaluate others’ arguments.[9] This blog post aims to cultivate intellectually honest discourse by equipping readers with the knowledge to recognize and address logical fallacies.[10]
A logical fallacy is “an argument that may sound . . . true but is actually flawed.”[11] A “logical fallacy . . . occurs when invalid arguments or irrelevant points are introduced without any evidence to support them. . . . Because fallacies appear to be correct . . . people can be tricked into accepting them.”[12]
At the basic level, there are two main types of logical fallacies: (1) informal logical fallacy and (2) formal logical fallacy.[13] “An informal logical fallacy occurs when there is an error in the content of an argument . . . .”[14] For example, the statement “I can’t possibly be wrong about climate change. After all, I’ve been studying environmental science for years!” is an informal logical fallacy because it relies on authority to reach a conclusion without first reasoning that the authority may be incorrect.[15] “A formal logical fallacy occurs when there is an error in the logical structure of an argument.”[16] For example, the deductive reasoning, “If I get a raise, I will have more money to spend. I have more money to spend. Therefore, I must have gotten a raise,” is a formal logical fallacy because the conclusion does not necessarily follow based solely on the fact that you have more money.[17]
Argumentum Ad Hominem
An Argumentum Ad Hominem occurs when “[r]ather than attacking the reasoning of the opponent’s argument, the . . . [arguer] attacks the person offering the argument.”[18] This type of logical fallacy “demonstrate[s] nothing about the validity or invalidity of the speaker’s argument or about the truth or falsity of the speaker’s conclusions.”[19] Even an unethical person can make sound arguments.[20] For example, if John states, “We should consider implementing stricter environmental regulations to reduce pollution and enhance the population’s health,” Mollie responds, “Why should we listen to you? You’re not an environmental scientist; you’re just a crooked politician taking money from evil lobbyists.” Mollie is committing an Argumentum Ad Hominem fallacy by attacking John’s status as a politician instead of discussing the argument itself.
The legal field recognizes Argumentum Ad Hominem logical fallacies “as irrelevant and unacceptable in legal argument . . . .”[21] Although, on occasion, these forms of logical fallacies are acceptable, such as when impeaching a witness or questioning an expert witness’ expertise.[22]
Generally, lawyers should avoid Argumentum Ad Hominem logical fallacies because they destroy civil discourse and break down productive discussions.[23] A Professor of Psychology at State University of New York at New Paltz states that “[a]voiding ad hominem attacks is, in fact, a foundational element of civil discourse . . . .”[24] Further, “[t]he fruitfulness of discussion depends largely on how well people are able to listen to one another and respectfully exchange ideas” and Argumentum Ad Hominem logical fallacies, when misused, contribute to making the “exchange of ideas more difficult.”[25]
When responding to an Argumentum Ad Hominem,you must first assess whether it is a genuine fallacy or a reasonable argument.[26] There are four dominant ways to respond to a fallacious Argumentum Ad Hominem attack. First, you may point out the irrelevancy of the argument and push the arguer to justify the relevancy of their personal attack.[27] Second, you may respond directly to the attack, replying as if it is a valid or reasonable argument.[28] Third, you may ignore the attack by “keep[ing] the discussion going” and “refusing to engage with the personal attack.”[29] Finally, you may acknowledge the attack and move on.[30]
To avoid the Argumentum Ad Hominem fallacy in your arguments, focus on the substance of the argument rather than the individual presenting it. In situations where Argumentum Ad Hominem may be justified, such as when impeaching a witness, it is best to “explicitly justify[] your use of the ad hominem argument, since doing so can help you ensure that its use is reasonable, and can help others understand the rationale behind it.”[31]
Ignoratio Elenchi
Ignoratio Elenchi, or the “straw man” fallacy, is “the fallacy of proving an irrelevant conclusion.”[32] Specifically, “[t]he fallacy consists of constructing an argument differing from the opponent’s and then, instead of attacking the opponent’s argument, attacking the argument of the straw man.”[33] This fallacy is employed against “someone else’s argument to make it easier to attack or refute.”[34] Politicians very commonly use the straw man argument.[35]
To illustrate, if David says, “We must add regulations to limit processed food to combat obesity, cancer, and disease,” and Karen responds, “David wants to shut down the entire food industry and leave people hungry. We can’t let that happen,” Karen is attacking a distorted version of David’s argument, thus creating a straw man fallacy.[36]
Straw man arguments in the legal context may not always be a fallacy. Notably, courts, “concerned with the consistency of the law . . . are interested in how a principle argued for in one context carries over to other contexts” may look at straw man arguments.[37] However, straw man arguments are best avoided because they are easy to refute.[38] Using a straw man argument hinders constructive debate and does not counter any relevant points an opposing party makes.[39]
The best strategy to avoid or counter a fallacious straw man argument is “to use clear and definitive language, with as little room for misinterpretation as possible. This makes it more difficult for your opponent to distort your stance and easier for you to correct them if they attempt to do so.”[40] However, if a straw man argument is used to attack your argument, there are three main strategies to counter it. First, you may put the arguer on the defensive and force them to explain how their argument is not fallacious.[41] Second, in some cases, it may be best “to ignore the distorted version of your argument . . . and continue to advocate for your original position.”[42] However, if the opposition continues focusing on the distorted view of your argument, it may be best to challenge them on their stance.[43] Finally, in rare instances, it may be best to accept the straw man argument and “defend[] the distorted version of your stance . . . .”[44] Although, it may be best to do this quickly as it could be challenging to get back to your original point.[45]
Moreover, when choosing whether to ignore, attack, or refute a straw man argument, it is best to account for the presence of an audience, such as a judge or jury.[46] In the presence of an audience, you are not persuading the opposing orator; you are persuading the audience. Thus, take a moment to “think about which . . . [strategy] will appeal the most to your audience” when choosing an approach to counter a straw man argument.[47]
Conclusion
In sum, a lawyer’s ability to understand and identify logical fallacies, such as Argumentum Ad Hominem and Ignoratio Elenchi, is a critical skill that will refine their argumentative abilities and enhance the persuasiveness of their legal discourse. Fallacies can undermine arguments, hinder constructive discussion, and prevent effective representation. Therefore, it is crucial for lawyers to recognize these fallacies in others’ arguments and avoid using them in their own. Although lawyers may occasionally employ logical fallacies strategically, it is important for them to understand the risks and be prepared to defend their stances with sound reasoning.
*Candidate for Doctor of Jurisprudence, University of Tennessee College of Law, May 2025.
[1]See Logical Fallacies, Univ. Writing & Speaking Ctr., https://www.unr.edu/writing-speaking-center/writing-speaking-resources/logical-fallacies (last visited Apr. 11, 2024) (“If you are arguing, avoid fallacies of thought because they create weaknesses in an argument.”).
[2] See Logic, Cambridge Dictionary, https://dictionary.cambridge.org/us/dictionary/english/logic (last visited Apr. 10, 2024).
[3] See Morton L. Schagrin & Nicholas Rescher, Fallacy, Britannica, https://www.britannica.com/topic/fallacy (last visited Feb. 29, 2024).
[4] See Kevin W. Saunders, Informal Fallacies in Legal Argumentation, 44 S.C. L. Rev. 343, 349, 353, 358, 359, 362, 363 (1993) (discussing how courts regularly accept arguments containing logical fallacies); see also Fallacies, The Writing Ctr.• Univ.of N. Carolina at Chapel Hill, https://writingcenter.unc.edu/tips-and-tools/fallacies/ (last visited Apr. 10, 2024) (“[F]allacious arguments are very, very common and can be quite persuasive, at least to the casual reader or listener. You can find dozens of examples of fallacious reasoning in newspapers, advertisements, and other sources.”).
[5] See Saunders, supra note 4, at 345, 381–82.
[6] See generally Ad Hominem, Dep’t of Phil., https://www.txst.edu/philosophy/resources/fallacy-definitions/Ad-Hominem.html (last visited May 16, 2024).
[7] See generally Ignoratio Elenchi (Irrelevant Conclusion); Straw Man; Red Herring; Non Sequitur, Introduction to Logic, https://philosophy.lander.edu/logic/ignoratio.html (last visited May 16, 2024).
[8] See generally Saunders, supra note 4, at 344–82 (discussing the relevance of informal fallacies in legal argumentation and utilizing examples from case law to illustrate each fallacy and consider its applicability within the context of legal discourse).
[9] See Logic for Lawyers: A Cheat Sheet, Am. Bar Assoc., https://www.americanbar.org/groups/government_public/resources/logic_for_lawyers/ (last visited Apr. 12, 2024) (“Understanding logical principles allows you to structure your arguments in a compelling way and find and explain weaknesses in your opponent’s arguments.”).
[10] “[T]he person who studies logic . . . and who has become familiar with the principles of logical thinking, is more likely to reason correctly than one who has not thought about the general concepts of reasoning.” See id. (citing Ruggero J. Aldisert, Logic for Lawyers: A Guide to Clear Legal Thinking 23 (3d ed. 1997)).
[11] Kassiani Nikolopoulou, Logical Fallacies | Definition, Types, List & Examples, Scribbr (Oct. 9, 2023), https://www.scribbr.com/fallacies/logical-fallacy/ (“[A] logical fallacy violates the principles of critical thinking because the premises do not sufficiently support the conclusion . . . .”).
[12] Id.
[13] Id.
[14] Id. (“i.e., it is based on irrelevant or false premises.”).
[15] This example demonstrates the informal logical fallacy known as appeal to authority. It occurs when someone tries to validate a claim by asserting that it must be true because it comes from an authoritative source or person. In this case, the person’s claim that they cannot be wrong about climate change because of their years of studying environmental science is based on the content of their expertise rather than the actual evidence or reasoning related to climate change itself. Thus, it is an informal logical fallacy because it relies on the content of the argument rather than a specific flaw in its formal structure. See id.
[16] Id.
[17] This example illustrates the fallacy of affirming the consequent, which is a type of formal logical fallacy. In a valid deductive argument, if the premises are true, the conclusion must also be true. However, in affirming the consequent, the argument structure is invalid because even if the premises are true, the conclusion does not necessarily follow. Here, this reasoning is fallacious because there could be other reasons besides getting a raise that would result in having more money to spend, such as receiving a gift, winning a lottery, inheriting money, or finding money unexpectedly. Therefore, even though having more money to spend could be a result of getting a raise, it does not necessarily follow that it must be the only explanation. See generally Affirming the Consequent, Logically Fallacious, https://www.logicallyfallacious.com/logicalfallacies/Affirming-the-Consequent (last visited May 15, 2024); Affirming the Consequent, Fallacy Files, https://www.fallacyfiles.org/afthecon.html (last visited May 15, 2024).
[18] Saunders, supra note 4, at 345.
[19] Id. (citing Irving M. Copi & Carl Cohen, Introduction To Logic 97 (8th ed. 1990)).
[20] Saunders, supra note 4, at 345 (“Even persons of wretched character sometimes offer valid arguments, and the fact that a conclusion coincides with the speaker’s economic or political interests has no bearing on the truth or falsity of the conclusion.”).
[21] Id. at 348.
[22] Id. at 348, 349.
[23] Jon Miltimore, 5 Reasons to Avoid Ad Hominem Arguments, Found. for Educ. Freedom, (Dec. 4, 2018), https://fee.org/articles/5-reasons-to-avoid-ad-hominem-arguments/.
[24] Id.
[25] Id.
[26] Itamar Shatz, Ad Hominem: When People Use Personal Attacks in Arguments, Effectiviology, https://effectiviology.com/ad-hominem-fallacy/ (last visited May 16, 2024).
[27] Id. (“Point out the irrelevance of the attack . . .by pointing out that the personal attack has nothing to do with the discussion at hand . . . . [It is] best to not become defensive when doing this, and if necessary, you should go on the offense and ask your opponent to justify why their personal attack is relevant to the discussion.”).
[28] Id. (“Respond to the attack directly[:] In some cases, you might want to fully address the ad hominem attack, even if it’s fallacious, because it could affect the outcome of the discussion in some way. You can do this by responding to the attack as you would to a reasonable ad hominem argument, or in a similar manner.”).
[29] Id.
[30] Id. (emphasis added) (“Acknowledge the attack and move on[.] This is similar to ignoring the ad hominem attack, except that you first acknowledge it explicitly before moving on with the discussion. This doesn’t necessarily mean that you have to agree with the attack; rather, it means that you have to show that you’re aware of it, which might look better than ignoring it entirely. To do this, you can use language such as, ‘I get it that you think that I’m X, but that doesn’t have anything to do with what we’re discussing here, so I’m not going to address it.’”).
[31] Id.
[32] Saunders, supra note 4, at 355 (citing Kobell v. Suburban Lines, 731 F.2d 1076, 1100 (3d Cir. 1984) (Aldisert, J., concurring)).
[33] Id. (citing Copi & Cohen, supra note 19, at 105); see also Itamar Shatz, Strawman Arguments: What They Are and How to Counter Them, Effectiviology, https://effectiviology.com/straw-man-arguments-recognize-counter-use/ (last visited May 15, 2024) (“There are countless ways to distort an opposing view when using a strawman. Common ways to do so include: [(1)] Oversimplifying, generalizing, or exaggerating the opponent’s argument[; (2)] Focusing on only a few specific aspects of an opponent’s argument[; (3)] Quoting parts of the opponent’s argument out of context[; (4)] Arguing against fringe or extreme opinions which are sometimes used in order to support the opponent’s stance, but which the opponent didn’t actually use.”).
[34] Kassiani Nikolopoulou, What Is Straw Man Fallacy? | Definition & Examples, Scribbr, (Oct. 9, 2023), https://www.scribbr.com/fallacies/straw-man-fallacy/.
[35] See Don’t Be Blown Away by the ‘Straw Man’ Fallacy, News Literacy Project, https://newslit.org/tips-tools/news-lit-tip-straw-man/ (last visited May 15, 2024) (“The straw man fallacy appears often in political debates, when speakers are focused more on impressing and persuading the audience than on changing their opponent’s view.”).
[36] In this example, Person B misrepresents Person A’s argument by exaggerating it to an extreme position (shutting down the entire energy industry), which is easier to attack than adding some regulations to limit carbon emissions to combat climate change. This misrepresentation creates a straw man argument that Person B can then argue against, rather than engaging with the actual proposal of adding regulations to limit carbon emissions. See Fallacies, Stanford Encyc. of Phil., (Apr. 2, 2020), https://plato.stanford.edu/entries/fallacies/.
[37] Saunders, supra note 4, at 356–7 (citations omitted) (“At oral argument in Thompson v. Oklahoma, counsel . . . argued that execution of a person who had committed murder while under eighteen years of age was per se cruel and unusual punishment because eighteen is the dominant traditional age of adulthood. When Justice O’Connor turned the questioning to the rule concerning abortions, which requires minors to be treated as adults . . . , she was not raising a straw man; instead, she was questioning whether the ruling requested by the petitioner in Thompson could be reconciled with the abortion cases or whether the Court was being led into an inconsistency.”).
[38] See Bad Arguments and How to Avoid Them, fs, https://fs.blog/bad-arguments/ (last visited May 16, 2024) (“A straw man argument is a misrepresentation of an opinion or viewpoint, designed to be . . . easy . . . to refute.”).
[39] See id. (“Bad arguments are harmful to everyone involved in a debate. They don’t get us anywhere because we’re not tackling an opponent’s actual viewpoint.”).
[40] Shatz, supra note 33.
[41] Id. (“[A]sk[] them to justify why they believe that the distorted stance that they present is the same as the one that you originally proposed; since the two are different, your opponent will either be forced to admit that their argument was invalid, or they will try to justify it by using even more fallacious reasoning, which you can then attack.”).
[42] Id.
[43] Id.
[44] Id.
[45] See id. (noting that the longer one goes down this route, the harder it will be to point out the oppopent’s reasoning).
[46] Id.
[47] Id.
tennesseelawreview.org 