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The Advantage Blog

  • Alexis Knutson


In 2009, John Lewis stood trial for shooting and killing a police officer in Philadelphia during an armed robbery of a doughnut store. In an unexpected turn of events, Lewis plead guilty to murder on the fourth day of jury selection, but it was up to the jury to decide whether it was committed intentionally or unintentionally, and thus determine the degree of murder and the appropriate punishment. After less than three hours of deliberation, the jury returned its verdict – guilty of first degree murder. Lewis was sentenced to death.

But in order for the jury to find him guilty of first degree murder, his actions had to be “willful.” A key piece of evidence in the case was surveillance footage that showed Lewis shooting the police officer. After watching the video in both real-­time and slow-­motion, the jury found that Lewis had acted willfully. Lewis argued on appeal that showing the video in slow­-motion made the act seem willful, drawn-­out, and deliberate when it actually was not. Between the time Lewis saw the police officer and the time he shot was just 2 seconds.

Although the Supreme Court of Pennsylvania upheld his conviction, researchers thought Lewis might be on to something. Early this month, researchers published results of a study that aimed to answer that very question – how does watching video in slow­-motion influence jurors’ perception of the crime? More specifically, does watching a video in slow-motion make an act seem more willful, deliberate, or premeditated?

Results – Slow-­Motion Bias

The short answer to this question is – yes. Watching a person act in slow­-motion gives the impression that the person had more time to think about their actions. It seems planned, careful, and intentional, rather than spur-­of-­the moment, panicked, or accidental. In a study that mirrors the Lewis case, participants watched surveillance video of a convenience store armed robbery gone wrong, ending in a person being shot and killed. Half of the participants saw the video in real­time, and half saw the video in slow­-motion. They found that those who saw the video in slow-­motion were four times more likely to convict the defendant than those who saw the video in real-­time.

When asked to estimate the amount of time the defendant had to think about his actions, the slow­-motion group estimated he had more time than the real­-time group. And in a follow-­up study, researchers even repeatedly told participants how much time had actually lapsed. Did that make a difference? No. These participants still thought more time had lapsed than the real-­time participants.

In another variation, some participants saw both real­-time and slow­-motion versions of the convenience store shooting, while others only saw real-­time video. Those who saw the slow-motion clip were still more likely to favor conviction of first degree murder (by about 50%) than those who only saw the real­-time surveillance.

Slow-­Mo in Civil Trials

This research had the aim of shedding light on the unintended impact of slow­-motion video on jurors judging criminal offenses, but it’s easy to see how it can be applied to civil cases as well. Civil cases are not immune to surveillance footage, iPhone recordings, and dash­-cam videos being admitted as evidence. These videos can be shown for the jury to decide if an act was intentional or negligent to the point of being unlawful. If videos are shown in slow­-motion, the likelihood is high that they will result in a higher degree of perceived wrongdoing.

Take for example a car accident where the plaintiff is suing the defendant driver for negligence. It’s plausible that there would be surveillance footage of the accident, particularly if the collision happened in a city. If the video of the collision is shown in real­time it may seem more like an accident. However, if the video is shown in slow­-motion, jurors may perceive that the defendant driver had more time to prevent the collision than he or she actually did, and be more likely to find this person negligent.

The jury would then consider damages. In the civil arena, it’s not yet known how slow­-motion videos could impact damages. But based on the current findings that slow­-motion video increases perceptions of intentionality and therefore guilt, a fair prediction would be that it would significantly increase damage awards. Damage awards are often driven by the level of anger, disgust, and outrage generated on behalf of the plaintiff, and the more intentional and egregious the defendant’s actions are portrayed, the more likely a large award will seem justified. Of course there are ways plaintiffs and defendants already try to frame time in a way that is beneficial to their case (i.e., making two events seem further apart or closer together, depending on what aligns best with their case facts). (One of our Senior Consultants, Ted Prosise, wrote an informative blog here about reframing an established theme in trial.) However, showing slow-motion video is one way to frame time that research has shown biases jurors against the defendant. Consider the impact slow-­motion video could have on your next case. If video is played in slow­-motion, the biasing effects on your jury could be substantial, and in some cases, be the difference between winning and losing.


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