By Dr. Ken Broda-Bahm:
Everyone who has ever served on a jury or watched a mock jury deliberate knows that emotions play a role. What you might not know, however, is that emotions also carry a bias. They're filtered and used selectively, owing to the fact that, in a particular legal context, some emotional responses are validated and some are discouraged. In the ongoing Boston Marathon bombing trial, for example, don't expect much in the way of sympathy for Dzhokar Tsarnaev. He's admittedly photogenic, but particularly once the panel has been vetted and "death qualified," the resulting jury is unlikely to be in the mood to apply emotional value to the young man, to give weight to his motivations or circumstances, or to believe the he was under the sway of a radicalized older brother. Instead, the jury's emotional consideration will likely be reserved for the victims. It is in our nature to infuse emotions into our evaluations, but in a legal context, some emotions are filtered out while other emotions are magnified.
Of course, some would say that this is exactly how it should be in the Tsarnaev case and others: Sympathy should be limited to those who deserve it. But the broader point is what I hope to emphasize in this post. The common perception of jurors sometimes simplifies the role of emotions: Of course they're emotional, they're only human. That broad perception misses the point that emotions will be filtered to the point that some emotions matter much more than others. A recent study explored this kind of selective relevance for emotions in deliberations. The article is published in Law and Social Inquiry (Lynch & Haney, 2014), is freely available online, and is also summarized in an article on AL.com. Focusing on a large number of video-recorded mock juries deliberating in a death penalty sentencing-phase trial, the researchers found that "Jurors strategically and explicitly employ emotion in the course of deliberation." More specifically, they showed that the filtering of emotional appeals creates a bias when jurors are choosing between life and death. "Pro-life jurors, in particular," they write, "appeared to have more difficulty expressing and using emotions than their pro-death counterparts."