A study on smuggling has disproved the myth that it is easy to spot smugglers by their evasive nonverbal behaviour. A disappointing finding? Not at all. It helps make law enforcement strategies more effective and also shapes future efforts to find out what techniques may be useful.

Popular films and behind-the-scenes television shows would lead us to believe that smugglers leak signs of nervousness, in much the same way that those same sources portray the behaviour of liars in general. Smuggling, after all, is just a specific form of deception. Just as some liars may exhibit nervous behaviour, so may some smugglers. Of course, nervous smugglers are more likely to be apprehended by customs officers, reinforcing beliefs that this is how smugglers behave. But what about all the smugglers who succeed in their crime undetected?

Deceptive behaviour

Decades of research into deceptive behaviour has revealed that there is, in fact, no ‘Pinocchio’s nose’ – no reliable, nonverbal behavioural cue indicative of deceit, however much we want there to be. While subtle differences may be detected between groups of liars and truth-tellers, these largely oppose the nervous behaviours popularly associated with lying and they tell us little about how to detect one liar at one point in time.

The problem is that there are several dimensions to what a liar may experience. These include anxiety about getting caught, which might lead to an increase in fidgety movements. But at the same time, the liar may well experience an increase in cognitive load, and an urge to control behaviour, both of which result in a decrease in movement. Combining these experiences with other factors – what the lie is about, what the consequences of being caught are, and the liar’s personality, experience, and relationship with the target – creates a myriad of moving parts that is hard to predict.

Professionals often argue that such findings are based on laboratory studies where the stakes are low for the liar and do not resemble real life, high-stake situations. It is true that the behaviour of the real-life, high-stakes liar, is hard to obtain in a form that may be examined. However, such studies do exist and corroborate the findings of laboratory studies. Hence, deception researchers have largely moved on from examining nonverbal behaviour in order to detect deceit. Instead, they have turned their attention to verbal differences, or developing techniques, such as manipulating the interview, in order to distinguish liars from truth-tellers.

The problem with detecting a smuggler is that there is only non-verbal behaviour to go on. This is true of any person with malicious intent among a crowd of people. Thus, as recent events have demonstrated, the problem of detecting the smuggler is an important one to solve.

The behaviour of the smuggler: A research study

In a study conducted at the University of Portsmouth, 52 participants were invited to see if they could evade detection when smuggling an item on a short ferry ride over to the neighbouring town of Gosport (each taking part individually). They were told that there would be ‘agents’ on the boat looking out for suspicious passengers and that they should try to avoid looking conspicuous and being detected. This was their only instruction. They could use any devices (e.g. mobile phone) that they wished to use, smoke, walk around, or sit wherever they wished. They were to meet with a contact near the ferry terminal on the other side. The experimenter gave the participant a mobile phone to contact her in the event of any problem, which had the added advantage of being able to track the participant’s precise location.

Two ‘agents’, posing as regular passengers and of whom one was disguised as a cyclist carrying a cycle helmet with small GoPro camera attached, also travelled on the ferry to Gosport in order to covertly film each participant. Half of the participants smuggled the item on the way to Gosport whilst the other half went to Gosport without anything to smuggle but received the item from the contact in order to smuggle it back. Hence half of the participants were covertly filmed when smuggling and half when they were not. All participants were interviewed at the end of their mission to discover what tactics they used to evade detection, and what thought processes they had. The videos, with participants’ permission, were analysed for various behaviours and then shown to another group of participants to see if they were able to detect who was smuggling and who was not.

Only eight of the participants realised that they were being filmed. How anxious participants felt about smuggling correlated with their anxiety levels measured in a personality questionnaire. Aside from this, there was nothing consistent about the tactics they employed, which varied wildly (for example, sitting amongst other people or sitting away from others, looking at everyone or avoiding all eye contact). Similarly, analysis of the video footage revealed no consistent behavioural cues. This finding was corroborated by the fact that participants in a further study were only 48% accurate at detecting who was smuggling and who was not.

The next step in detecting smugglers

As anticipated, participants varied wildly in their behaviour and tactics when smuggling. While it is true that the participants in this study were probably not practised in the art of smuggling, based on deception research, we assume that this reflects real life where some may exhibit detectable nervous behaviour and many will not. Hence the most effective solution, as in other realms of deception research, is to devise an easily implementable technique to distinguish between smugglers and innocents. For example, by having ‘agents’ approach and stand uncomfortably close to the participant and appear to detect them, but without saying as much, to see if doing so prompts a different reaction in smugglers to those who are not smuggling. This is what we are currently investigating...