The Psychology of Deception: Understanding Why People Lie and How Private Investigators Detect It (And You Can Too)

• March 14, 2023
• Urban Spy California, San Diego California
• no comments

Deception is an all-too-common and unavoidable aspect of everyday human interaction and is something we’ve all both suffered and benefitted from at one point or another. There are numerous reasons that one may try to deceive another, but deception plays an interesting role from the perspective of a private investigator. While on the surface, attempts at deception may seem like an obvious roadblock to the work of a private investigator, identifying and understanding the reason and purpose of one’s deception can be instrumental in revealing more about a person’s character and provide more insight into their nature than the truth ever could. Let us first identify and discuss some of the most common reasons for deception:

Why People Lie:

The primary, and most obvious, reason for people to lie is to avoid negative consequences. This behavior can be observed in children as young as 3 years old! It’s by no means a behavior reserved for the developing brain, however, as intentional deception is regularly weaponized by people across all cultures and facets of society to avoid repercussions (if their deception is successful, of course). This could present itself as a criminal lying about their whereabouts at the time of a crime, a cheating spouse lying about their whereabouts at the time of an affair, or a coworker lying about their whereabouts at the time of a workplace accident. People lie a lot about their whereabouts.

Another common reason for people to lie is in attempt to gain competitive advantage. This form of deception appears subtly as exaggeration of truth or boldly as outright fables. People may implement this type of deception on job applications, in interviews, on first dates, or when trying to get ahead of difficult news. This deception is generally used as a tactic to make oneself appear greater than they are or to control the flow of information in a situation.

There is also what is sometimes referred to as an altruistic lie. It may feel uncomfortable to some to think of a lie as being altruistic, but I’m sure we’ve all told a friend before that their horrible new haircut looks great or our children that their crayon scribbles belong in the Louvre. The most innocuous form of deception, altruistic lies are told to try and avoid hurting someone’s feelings or protect them from a truth we deem as otherwise too painful. In this instance, the deception is often seen as harmless and excusable, but it is a form of deception nonetheless.

If the waters of duplicity aren’t murky enough already, it gets even trickier. Oftentimes, the act of lying is subconscious and can occur without the person even realizing that they are doing it. Our memories are fundamentally imperfect – this is a widely studied and understood phenomenon that impacts criminal court cases daily. Not only do we lose particulars of events in our memory and subconsciously fill in the gaps with inaccurate details, it is also possible using the act of subtle suggestion to implant completely false memories entirely that feel as real as any other. With this inherent unreliability of our memories, deception can appear as a result of misunderstandings, misrememberings, or omission of details that have truly faded away over time. Oftentimes, the act of lying is subconscious and can occur without the person even realizing that they are doing it. Did you catch that?

How We Can Catch Them:

Before you retreat to a cave to hide from the tidal wave of lies barraging you every day, rest assured that defensive measures exist to detect and combat the fraudulent floods. Private investigators regularly implement various tactics to identify dishonesty which, with enough time and practice, become almost second nature. You’ve already started on the first tactic, which is identifying the various reasons why people lie. Understanding the logic behind deception and realizing when such an incentive exists can oftentimes be your first indicator that duplicity is likely. It is also important to acknowledge that these incentives sometimes only need to exist from the perspective of the deceiver to provide the proper cocktail of ingredients for a lie to rear its head. By this I mean that even if you feel there are no actual negative consequences to avoid, no competitive advantage to gain, no feelings to spare – only the other party needs to feel that there are in order for them to potentially incorporate some kind of deception.

Of course, we’re all faced with the opportunity to lie almost endlessly in day-to-day life, but having the ability or justification for lying does not mean that person is sure to do so. So once you’ve seen the warning signs, what are the next level methods of deception detection? Observation of nonverbal cues. When someone is lying, they may display certain physical signs, such as avoiding eye contact, repeatedly flaring their nostrils, fidgeting, or touching their face. However, it’s vital to note that these cues can be influenced by other factors, such as stress or nervousness, so it’s important to look for a cluster of cues, or noticeably uncharacteristic behaviors, rather than relying on a single one, and to of course take into account the strength of potential incentives and weigh that against what you already know of their character.

Let’s take it a step further: we know they have reason to self-justify a lie, we observe uncharacteristic fidgeting and shiftiness when discussing a certain topic. We’ve got the subtle whiff of deception floating in the air, but it’s only a whisper. We need to dig deeper, and the next step may involve implementing some forms of deception of our own. Once we suspect a lie, the most strategic move is to implement a strategic line questioning without revealing how much we actually know about an event. The idea is to use various interviewing techniques to assess the credibility of a person’s story, find them contradicting their own narrative, or catch them stating outright mistruths. It’s important to never outright state how much you actually know about the event going into it or it will make it that much easier for them to talk around or explain things away. Using open-ended questions makes this process easier, rather than asking yes or no questions, as it provides them with the opportunity to start digging the hole that they will bury themselves in. If they are trying to deceive you, not only will making them provide more details put them on the spot and force them to try and think more quickly, it will force them to also try and remember all of the lies they’ve told thus far and sort through how they all fit together logically in real-time. Easier said than done, it is also important to remain calm and level-headed during this step. Getting overly emotional or worked up may cause you to reveal your hand too early, or tip them off that you’re trying to catch them in a lie. If they understand your intention, they will raise their guard and speak more carefully. If they are under the impression that you’re on their hook, they will typically lie more carelessly and respond more “from-the-hip”, as they will generally be trying to keep the conversation casual to just avoid suspicion in the first place.

These are all useful techniques for the average person to implement when they suspect deceit, but there are additional tactics that can be used when the stakes are higher, such as in criminal investigations or background checks for high-ranking government positions. In these cases investigators may utilize various forms of technology to increase the likelihood of identifying deception with none of the subtlety of previous methods. You may have heard of some of these before, like the notorious polygraph test that makes routine appearances on day-time tabloid talk shows like Maury or Jerry Springer (dated references at this point, I know). These tests can measure physiological responses, such as changes in blood pressure, heart rate, and perspiration in response to a series of questions. Additional software tools like voice stress analysis can be used to analyze variations in a person’s voice to detect stress and may indicate some form of deception. It’s important to note that, while these may be considered surefire ways to catch dishonesty, polygraph tests really only measure the body’s response to questioning which can muddy the results and be inconsistent at times, although their 80-90% accuracy estimates certainly beat the average person’s approximately 55% accuracy estimate in detecting lies. These testing methods can be useful to law enforcement and private investigators, but can be either difficult to find, cost-prohibitive, or impossible to rationally implement for most interpersonal disputes in everyday life, but I would be remiss to neglect mentioning them.

The Bigger Picture:

Keep in mind that detecting deception is not always a straightforward process, and that even the most experienced investigators can be deceived. Not everybody lies with the same strength or with the same frequency. There are certainly people who are adeptly skilled at hiding deception, that lie without reason, or that expertly craft concrete narratives to explain away every inconsistency. However, by understanding the psychology of deception and using a combination of observation, questioning, and technology, private investigators (and you) can increase the chances of detecting deception and uncovering the truth.

As a caveat, it is also worth noting that just because someone is lying does not mean they are guilty of a crime or that their intentions are malicious. As stated previously, it is also common for people to “lie with good intentions” or to lie subconsciously, or to simply misremember anything from major events or minor details. That being said, being lied to is an oftentimes painful process on a personal level and can be tricky to navigate without experience in doing so effectively and with a level-mind. Deception is a complex and multifaceted aspect of human behavior that private investigators encounter frequently in their work – it’s the job of private investigators to gather evidence and make informed judgements, to weigh likelihoods and justifications, incentives and signifiers, claims and certainties, and to pass that information along to their clients.

Hopefully this piece has helped you understand some of the underlying psychology behind deception and some ways you can meet it on its face. I am 100% certain that by following this guide you will be able to identify without fail every lie spoken to you from this point forward and catch all of your friends, family, and coworkers in every form trickery they could possibly try to use against you; you are sure to become the shining beacon of truth to light their lives, and they will adore you for it ceaselessly. Am I lying to you? Of course not.