By Jason Weber
Have you ever wondered why people fall for scams, cling to toxic relationships, or trust everything they hear on TikTok? While there are various reasons for these behaviors, one intriguing psychological concept you may not have heard of is the Truth-Default Theory. In this article, I will explain this theory and its relevance to investigations.
Wired for truth
Professor Timothy R. Levine, the creator of Truth-Default Theory (TDT), defines the theory as:
“The central idea that people default to truth, or at least truth as they know it. Generally, humans communicate honestly unless there is a reason to deceive others, and humans passively accept incoming communication as honest unless they have a reason to suspect otherwise.”
At first glance, this idea may seem a bit obvious — of course people lie for a reason — but take another look at the second half of that quote. What Levine is saying here is that when you hear a piece of information, you typically believe it unless you have a reason to be suspicious.
You may read this and think, “That doesn’t apply to me. I don’t believe everything I hear.” But let’s break this down at its most basic. Our world needs truth default to function. Imagine you’re at Starbucks getting ready to pay for your morning caffeine fix. The barista says, “That’ll be $6.” Do you cast doubt on her honesty? What if the price is $5 and she’s skimming off the top? What if she input the wrong order? Do you begin to question each scenario to determine if she has told you the correct price? Of course not.
In reality, most of us accept such information at face value. This inherent trust keeps society moving. If we approached every statement with skepticism, continually questioning the truth of what we hear, our daily interactions would become laborious and impractical. This default to truth allows us to navigate our lives with a certain level of trust, making assumptions that generally hold true and facilitating smoother social interactions.
This concept is crucial because TDT, backed by psychological research, suggests that people are honest most of the time. Imagine if we were always suspicious and believed everyone was lying; our lives would be significantly more challenging, and we would often be mistaken. Trusting others by default allows us to navigate our daily lives more effectively and build relationships based on mutual trust.
Beyond suspicion: Truth-Default Theory in police investigations
When it comes to questioning the truth, the one group of individuals who don’t need a reminder are police officers and investigators. Many in law enforcement believe they’re constantly getting lied to, and often their suspicions turn out to be true. However, now armed with the basic information about Truth-Default Theory, does this constant suspicion hold up? Let’s break it down.
The first tenant of the theory states: “Generally, humans communicate honestly unless there is a reason to deceive others.” In criminal investigations, there are endless motives for deception. A subject might lie to avoid prosecution, to protect another family member, or a victim might lie out of shame or embarrassment. Investigators are trained to be vigilant for deception, however, TDT argues that investigators should also be attuned to the truth. Constantly searching for lies in predominantly truthful communications may lead to disbelief of a genuinely truthful person.
The second tenant states: “and humans passively accept incoming communication as honest unless they have a reason to suspect otherwise.” This is where trouble can happen. Despite being trained and taught to look for deception, we are fighting against human nature. In practice, this means if a crafty subject mixes a deceptive statement around other truthful statements, spotting the lie can be challenging. Psychological research has shown that even trained police officers struggle to detect deception at the moment at a better than 50/50 chance.
Many trainings and “lie spotters” teach that body language and non-verbal communication give away deceptive individuals. The reality is much more nuanced. Body language is highly individual, and there’s no one magical behavior that indicates deception. Furthermore, during an interview, investigators are inundated with information, making it challenging to process everything at once. Truth-Default Theory and other interviewing research suggest that lies are often uncovered once the interview is over and reviewed, highlighting the importance of gathering verifiable information and detailed narratives.
Incorporating Truth-Default Theory into interviews
While Truth-Default Theory has a profound impact on all areas of our investigations, there’s none more prevalent than in interviewing. Investigators gather most of our information by interviewing victims, witnesses and subjects. Investigators need to understand how to best gather and decipher the information to make the best decisions for their cases. This is accomplished by being aware of TDT and questioning in ways that incorporate the theory.
Now to the part that everyone wants, what’s the practical information and how does this help me? Below, I’ll offer three interviewing tips that incorporate TDT.
1. Focus on gathering detailed narratives
Many investigators see “getting the confession” as the goal of an interview. When interviewing with TDT in mind, the goal shifts from getting a confession to gathering detailed narratives. Most lies are discovered after the fact by verifiable evidence. Thus, investigators should focus on asking open-ended questions that allow the subject to talk, asking for specific and verifiable details, and building rapport to encourage the subject to speak. Asking open-ended questions is like giving someone an essay test, while asking yes/no questions is more like a multiple-choice test. Just as it’s easier to guess the answer on a multiple-choice test, it’s easier for someone to deceive with a yes/no question. Open-ended questions make it much harder for someone to deceive you.
A verified lie can be as valuable as a confession within a criminal trial. By having a deceptive subject speak more, there’s a higher likelihood that they slip up and tell something that can be proven false.
2. Ask unexpected questions
Levine explains in his book that most individuals who lie often create a “Lie Script” prior to engaging with law enforcement. They typically rehearse what they plan to say and attempt to think of questions they may be asked. They do this to feel more comfortable during the encounter, much like how many of us prepare for job interviews. However, as in a job interview, the most challenging questions are often the unexpected ones. If you pose a question that catches the liar off guard, they may struggle to provide a convincing answer or respond in a way that can be easily contradicted by evidence.
The specific unexpected questions you might ask are going to be dependent on the case. Some examples of unexpected questions could be:
- Asking for specific details of a place, event, or object beyond the typical, who, what, when, etc.
- Asking what emotions or feelings the person was experiencing during the event.
- Asking the subject to draw a sketch of the area or object.
- Asking what another person (at the same event) may have seen or been feeling.
3. Explicitly ask for verifiable details
For many, interactions with the police or investigators are rare. People often form their perceptions of law enforcement from television, where police are portrayed as omniscient, possessing all the facts and interrogating suspects rather than gathering information. However, witnesses may not consider the specific details investigators need, assuming that certain information is already known. To address this, when conducting interviews, start by instructing the subject to provide verifiable details throughout their account. For example, tell the individual to mention if they got a receipt with their purchase or if they saw cameras in the building. After they’ve finished, carefully review their narrative for places where such details can be corroborated.
Providing these instructions benefits your investigation in two ways. Firstly, with a truthful subject, it encourages them to share details they might not have considered initially. This can provide you with additional facts and information to strengthen your case. Even in situations where verifiable details are unavailable, such as when a gas station lacks security cameras, observing how the subject attempts to assist can be telling. A truthful person may still try to offer ways to verify their information, demonstrating their cooperation and credibility.
Conversely, with a deceptive subject, these instructions create what’s called a “Liar’s Dilemma.” When faced with these directions, the liar is left with two choices, both problematic for them. The first option is to fabricate details, hoping the investigator won’t uncover the falsehoods. The second is to avoid providing any verifiable information, which also raises suspicions. This dilemma forces the liar into a corner: providing fake details that can be checked or offering no details, both of which can undermine their credibility and suggest a lack of truthfulness.
Conclusion
Truth-Default Theory offers valuable insights into human communication and behavior, particularly in the context of police investigations. While Truth-Default Theory may not be widely known or discussed in interviewing courses, its practical implications are significant. By incorporating the principles of TDT into their investigative practices, officers and investigators can enhance their ability to discern truth from deception, ultimately leading to more effective and reliable outcomes in their cases.
Below are links with additional information, as well as citations to support the information I’ve discussed above.
Additional information
Bibliography
1. https://timothy-levine.squarespace.com/truth-default-theory
2. Levine TR. (2020.) Duped: Truth-Default Theory and the Social Science of Lying and Deception. Tuscaloosa, AL: University of Alabama Press.
3. Ekman P. (1991.) Why kids lie: How parents can encourage truthfulness. Penguin.
4. Bond CF, Jr., DePaulo BM. (2006.) Accuracy of deception judgments. Personality and Social Psychology Review, 10, 214-234.
5. Brandon S, Wells S. (2018.) Science-Based Interviewing.
6. Palena N, Caso L, Vrij A, Nahari G. (2021.) The verifiability approach: A meta-analysis. Journal of Applied Research in Memory and Cognition, 10(1), 155-166.
About the author
Jason Weber is a Special Agent with the Tennessee Bureau of Investigation (TBI), currently assigned to the East Tennessee Criminal Investigation Division. In this role, SA Weber handles major cases, including homicides, officer-involved shootings, crimes against children, and significant theft investigations.
SA Weber has a strong commitment to advancing the field of law enforcement through behavioral science, and he is dedicated to promoting the benefits of behavioral science to law enforcement officers nationwide. As an instructor, SA Weber specializes in teaching Interview and Interrogation techniques, focusing on how psychological principles can enhance the effectiveness of interviews. SA Weber holds both a Bachelor of Science and a Master of Science degree in Psychology from the University of Tennessee at Chattanooga and is a Certified Forensic Interviewer through the International Association of Interviewers.