U of T news
  • Follow U of T News

Can you tell a trustworthy from an untrustworthy face? The answer may surprise you

Research shows an inherent trustworthiness bias, which could mean the difference between life or death

Professor Nicholas Rule of U of T's Social Perception & Cognition Lab

Can an apparent look of trustworthiness make the difference between life and death for convicted felons?

Research by Nicholas Rule and John Paul Wilson of the department of psychology suggests it can. And their work has captured the attention of readers from The Economist to the Daily Mail.

“People have really strong intuition about who is trustworthy and who isn’t,” says Rule, principal investigator of U of T’s Social Perception & Cognition Lab. “When you test it empirically, people think they can tell when others are lying, but they actually can’t.”

U of T News spoke to Rule and Wilson, a postdoctoral fellow at the Lab, about a headline-generating study published in Psychological Science in which viewers of mug shots of Florida convicts ranked those given life sentences as more trustworthy in appearance than those on death row. 


Why did this study get so much coverage in the media?

Rule: It is timely, especially in the American context. There is a debate in Nebraska over the death penalty and the case of the Boston marathon bomber who was sentenced to death. President Obama is pushing for reform in prisons and less harsh sentences. Even Republicans are coming on board. The legal system is on people’s minds, especially as the Americans move to the presidential election. It brings up issues around morality, ethics, what it means to reform people, and the criminal justice system in general.

What is the significance of your research?

Wilson: It’s a demonstration of a disturbing phenomenon. We haven’t necessarily isolated any specific ways to curb bias, but it’s sensible to look at this work and use it to inform ourselves. We would like people to be aware of the work because we are all susceptible. The way we see and treat other people is based on biases. Reducing them starts with awareness.

Is there a lesson for Canadians?

Rule: We don’t have the death penalty, so no one is getting executed here in Canada, but the larger message is that in courts, people are using information that is based on heuristic and superficial approaches. Defendants are more likely to be found guilty if they look a certain way, or get more severe sentencing if they look guilty.

We might want to ask if we want judges and jury members to see the defendant. I think that [not seeing the defendant] would create a fair system by which people would make a fairer judgement.

Does the bias you discovered have other implications?

Rule: Individuals have individual biases and these are mostly idiosyncratic. But the reality is that political leaders modify their behaviour so that people will perceive them in a certain way. In my opinion that’s the wrong way to go. We should accept the fact that people have biases and be more aware of those biases. The problem is that people operate on the idea that their biases are objective when they are not. When those biases aggregate and come together they can be harmful, particularly when they become the basis of policy. We hope this research will raise awareness of bias and the need to monitor it.

Could you describe the methodology of the project?

Wilson: First we had to download the images and information about the convicts on death row in Florida, then do the same for those convicted of murder and sentenced to life in prison. We recruited subjects online who were not aware of the status of these people or even that they were convicted criminals. We didn’t tell them anything about the people that they were seeing, although some assumed that the photos were mug shots and that the people were probably convicted criminals. One group rated both those sentenced to death and those sentenced to life on traits of trustworthiness and untrustworthiness. We had a total of 742 faces in the first study. Each person rated around 100 of those faces. Our second study was of people wrongly convicted who had been sentenced to death or to life in prison. They were later exonerated with the help of the Innocence Project, but even in these cases, trustworthiness was associated with their previous sentencing outcomes.

What else are you working on in the Social Perception & Cognition Lab?

Rule: One postdoctoral student is working with me right now on perception of leadership from facial cues. We also have a study coming out about perception of health. People are very good at determining how healthy someone is from certain distinctive cues. For example, how much red or yellow hue you have in your skin relates to your immune system. People are able to pick up on these cues and they are reliable markers.