I have written about deception before e.g., about the changes in pronoun use that people use to distance themselves from events, and the disproportionate number of disfluencies – “Umms”, “Errs” etc. – that are present in deceitful statements. However, I have not written about the structure of deceptive statements i.e., how a person structures what they say, when engaged in deception. In this article I want to take a closer look at the structure and content of deceptive statements. The structure of deceptive statements is one of the few commonalities shared by those who attempt to engage in deception e.g., Some studies (Vrij et al., 1997) for instance have found that increases and decreases in hand movement occur at almost the same rate when people engage in deceit; 52 % of people increase hand movement when lying, whereas 48% decrease it. This illustrates that there are few universal cues to alert us when someone is engaged in deception i.e., different people lie differently. However, there are certain things that do appear to be largely universal, and the way that a deceptive statement is structured is one of these, and by comparing them to the way truthful statements are structured, we can/may start to understand when someone is attempting to deceive us. 

If someone is giving us a truthful account of an incident/event, or how they spent their time etc. then they will tend to focus on getting to the main part of their story relatively quickly. The opening part of truthful statements tend to be very light on details, as the emphasis is on recounting the “Main Event”. The reverse is generally true for untruthful statements. If someone is engaged in deception, they want to establish trust and belief before they get to the lie itself. By over-detailing things at the start of a statement they can demonstrate that they want you to know everything and that they’re not holding anything back. Being very detailed in their account early on allows for them to do this, especially if their details can be easily corroborated and established as facts e.g., someone giving an account of what they did yesterday afternoon, might mention that they bumped into someone you know (which they did and can be checked), and then spends a long time detailing what they talked about, which is completely irrelevant to the “Main Event” of the story. By using a lot of truthful statements early on it’s easier for someone to keep track of their story, as they don’t have to remember too many untruthful things, which may trip them up when they have to recall their account. An over-detailed, truthful introduction/opening can be used to bury a few untruths, that can be hidden in the main event. Basically, irrelevant but truthful details are used as a means of deemphasizing untruthful details later on. If someone takes an overly long time to get to the main event and overloads their introduction with a large number of truthful but irrelevant facts/details, then there is a good chance they are attempting to engage in deception.

A person attempting to deceive may also do a lot of auto-correction of the details in their introduction e.g., if a person is trying to hide what they were doing yesterday afternoon, they might say that they left their house at 2:00 PM, and then correct themselves by saying it was actually 2:15 PM, and then correct themselves again to say it was 2:20 PM etc. This is a very simple way that they can communicate to you that they want to be completely open and honest with you, and make sure that you understand that it is their desire for you to know the complete and honest truth. In actual fact whether they left the house at 2:00 or 2:20 pm is pretty irrelevant to what they did that afternoon (something which accounts for a much greater span of time). This desire to appear accurate also prevents their account from coming across as a bit vague. Take two accounts, one deceitful, one truthful. Let’s say you wanted to know what somebody was doing between 1 and 3 PM, and you ask them this. One account/story is: “I went to the pub at 12:30 pm, no I’m wrong about that it was 12:45 pm, because I was intending to leave the house at 12:30, but then I remembered I had to move some clothes that were in the washer to the dryer. It took me about 10, maybe 15, probably more like 20 minutes to walk there. So, I must have got there sometime around 1 pm. I had 3, no sorry 4, beers and then left around 3 pm. No, it was 3:15 pm because I watched the first few minutes of the match, and then I walked home.” The other is: “I went to the pub sometime around 1 pm, I had a few drinks, and then left sometime after 3 pm and was home soon after.” The truthful account is concise, communicates the right amount of detail, whereas the other is too detailed, and is probably missing a key fact or event/incident. Omission is one of the four types of deception the other three being: Falsification (outright lies and contradiction), Exaggeration (modifying facts), and Misleading (misdirection using irrelevant information).

Unsolicited details should also be concise and in context. Compare the statement, “The man who pulled the gun on me was wearing a grey suit”, with, “The man who pulled the gun on me was wearing a cheap grey suit. The sort that somebody without any style or class would think looked expensive, but really just showed how little taste they actually had.” This introduces the element of “genre” into detecting deception. If the person you are talking to, is someone who is creative and humorous in the way they re-tell events, their style or genre might be one where they scatter jokes and humorous observations into their accounts of events. This should be a consideration that you take into account when trying to assess whether somebody is engaged in deception.

As Hartwig and Bond (2011) state, there is no, “Pinocchio’s Nose” to indicate when somebody is lying. There are so many “myths” concerning deception, such as people not making eye-contact when lying, or looking up and to the left when engaged in deception, or show nervousness or unease when being untruthful etc. The reality is that different people, perform differently, when engaged in deception and so rather than investigate the individual, we should investigate the lie, and that means largely looking at its structure and then at its content. It has been found that when we are asked to detect a lie we are – without training – about as good as chance. However, if we are asked to identify if somebody is thinking too hard about what they are saying (a sign of deception), our detection rate rises to about 75%. Asking the right question, with the right knowledge and understanding, is the key to detecting deception.