Truth Bias

Researchers have consistently found that people are poor at detecting deception. One reason for this poor performance is the reliance on heuristics or simple decision rules when processing social interactions. Heuristics are mental shortcuts or rules of thumb based on experiences that often result in a quick and satisfactory outcome with minimal cognitive effort. One of these heuristics is the truth bias. The truth bias is the presumption of truth in interpersonal interactions and the tendency to judge an interpersonal message as truthful rather than deceptive, irrespective of the actual truth of the message. Communicators are initially assumed to be truthful, and this assumption is possibly revised only if something in the situation evokes suspicion. The truth bias is important for maintaining relationships and increasing intimacy because accusations of deception are damaging to relationships.

The truth bias is robust and widely documented by research involving people interacting with both friends and strangers. Although researchers have consistently found a strong truth bias in laboratory experiments, they have argued that the truth bias is probably even stronger in [Page 905]naturally occurring settings because simply asking people to make judgments about deception in a lab context may arouse suspicion and lower a person's natural truth bias. The truth bias also is stronger during face-to-face communication, when people are interacting with friends rather than strangers, and when people do not know that the experimental task involves detection of deception.

Cognitive heuristics like the truth bias are learned through experience or conventional beliefs. Relying on heuristics reduces cognitive effort and simplifies decision making; while heuristics can often lead to a correct decision or judgment, they can result in biases and faulty judgment. In the case of the truth bias, the large majority of naturally occurring interpersonal interactions are truthful, so reliance on the truth bias generally results in accurate judgment with minimal need to assess the interaction for deception.