We think anger is a sign of guilt, but it may actually be a better sign of innocence

We're famously bad at spotting lies (well, most of us are; skilled liars are better). That doesn't stop us thinking we know when someone's spinning us a line, of course.

Now a new paper in Psychological Science reveals that we take an angry denial to be a sign that the accused is lying. And yet, Katherine A. DeCelles at the University of Toronto and colleagues also report, anger in response to a false accusation is in fact a sign of innocence.

In initial studies on more than 4,000 online participants, the team established that anger is consistently taken as a sign of guilt. This held across a variety of contexts, including a fictional courtroom situation with an accusation of armed robbery, and also scenarios involving accusations of infidelity and theft.

In each case, the participants read about how the confronted individuals reacted, and made judgments about their guilt. Fictional people who'd made angry denials were taken to be guiltier than those who'd made "irritated" denials (characterised by a raised voice and less vehement protests), and they were in turn taken to be guiltier than those who'd calmly professed their innocence.

Perhaps, though, professionals who often have to make guilt judgements in their jobs react differently? A fresh study on 136 such people, including fraud investigators, police and lawyers, found this not to be the case. These participants judged that an employee described as having reacted angrily to an accusation of theft was guiltier than one who reacted calmly. In fact, the "angry" employee was considered just as guilty as a "silent" employee who'd refused to respond when confronted.

If anger actually is a sign of guilt then these results would suggest a useful clue to truthfulness, of course. However, in a subsequent study, participants who were asked to reflect on situations in their own lives reported feeling and also displaying more anger when they had been falsely vs justly accused of a misdeed. It didn't matter whether the deed was trivial (taking a room-mate's food, for example) or serious — cheating on a spouse, say, or workplace misconduct.

In a final study, participants took part in an in-person lab-based experiment in which some were falsely accused of making mistakes on a text-based task; this group reported feeling angrier than those who were correctly accused of making errors.

Overall, then, as the researchers write, anger does seem to be used as invalid cue of guilt while being a valid cue of innocence.

It's important to understand what is — and isn't — a genuine sign of innocence vs guilt in all kinds of situations, of course. But there are a few reasons to be cautious about drawing strong conclusions from this new work.

For example: the "angry" denials that the participants read in the initial experiments were pretty angry, featuring explicit language and expressing outrage. Their anger level was a lot higher than that reported by participants in the latter studies in response to being falsely accused themselves. Even those who'd reflected on being falsely accused of a serious transgression did not report such extreme anger.

Hamlet springs to mind, and Queen Gertrude's classic line: "The lady doth protest too much…" An emotional over-reaction that doesn't match the scale of an accusation might yet be a sign of guilt; at least, this paper doesn't show that it isn't.

However, it's true that people who reacted with irritation were taken to be guiltier than those who responded calmly. So until more work is done in this area, it seems worth at least trying not to use someone's anger level in response to an accusation as a sign of guilt.

Further reading

– Anger Damns the Innocent

About the author

Emma Young (@EmmaELYoung) is a staff writer at BPS Research Digest