Aroused Suspicion

Research on Aroused Suspicion

Research on how suspicion affects accuracy has shown inconsistent effects; thus, not fulfilling expectations of increasing accuracy. Some research has supported a curvilinear effect, in which moderate increases in suspicion resulted in increases in detection accuracy, but low levels and high levels of suspicion resulted in decreases in detection accuracy. This research was conducted among romantically involved couples, yet linear relationships were found when this research was replicated with strangers. Among strangers, as suspicion increased from low- to medium- to high-manipulation levels, the lie accuracy rate steadily improved, whereas the truth accuracy rate gradually decreased.

These studies that found separate effects on truth and lie accuracy came after the discovery of the veracity effect. In other words, individuals are better at detecting truths than they are at detecting lies. However, by separating out truths and lies, it may be easier to determine the differential effect of suspicion on accuracy. Because it can thwart the truth bias, but not create a lie bias, the result would be an increase in accuracy in detecting lies and a subsequent reduction in the accuracy of detecting truths.

The way that suspicion has been induced may explain the mixed findings with regard to aroused suspicion and accuracy. Some researchers have used two levels of suspicion, low or high, or the presence or absence of suspicion. Other researchers have used three levels of suspicion: no suspicion, low level of suspicion, and a high level of suspicion. Research using three levels of suspicion has tended to show either the curvilinear or linear effects of suspicion on detection accuracy. Thus, when suspicion is induced at different levels, the picture of its potential influence on accuracy becomes clearer.

Further, suspicion may lead to increased confidence or an overconfidence in the ability to detect deception. In a study examining police officers, it was found that when police officers were highly suspicious of a potential criminal, they then began to believe that their suspicion was a certainty. With increased certainty that an individual committed a crime, it may become more likely that accused individuals will enact false confessions.

Because of the relationship between suspicion and truth bias, much of the research on suspicion has focused on whether it can reduce the truth bias, or the tendency to believe that a message is truthful, even in the presence of information that shows the information to be false. This has been the most robust and consistent effect across aroused suspicion studies. In studies with strangers, friends, and romantic partners, increased aroused suspicion has led to a reduction of the truth bias.

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