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Fake Video Can Convince Witnesses to Give False Testimony

Wired reports on a fascinating new study showing how eyewitness memory can be influenced by video.

Participants in the study were paired with a partner (who was actually part of the research team) to play a gambling-based computer game. The participants bet money on their own ability to answer multiple choice questions. The game relied on participants to honestly pay back money they’d earned when they got a question wrong.

After they had finished with the questions, the participants were told that their partner had cheated, even though the partner hadn’t. One group of students were then shown a video that had been digitally altered to make the partner look as if he had actually cheated. Though they were told to only report their partner if they were 100 percent sure he had cheated, and that the partner would be punished based on their decision, about half the participants who viewed the video still reported their partner for cheating. The second group wassn’t shown the video, but only told of its existence. Just 10 percent of them still reported their partner for cheating.

The scientists offered several possible explanations for why video had such a strong effect on memory. “First, people still view photos and videos as reliable records of the past,” psychology graduate student Robert Nash wrote in an e-mail. “Around 75 percent of the people who participate in our research know something about photo or video editing software, yet many of the people in this study were convinced by our edited footage.

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