A counterintuitive truth from Phys.org: Why too much evidence can be a bad thing.
“If many independent witnesses unanimously testify to the identity of a suspect of a crime, we assume they cannot all be wrong,” coauthor Derek Abbott, a physicist and electronic engineer at The University of Adelaide, Australia, told Phys.org. “Unanimity is often assumed to be reliable. However, it turns out that the probability of a large number of people all agreeing is small, so our confidence in unanimity is ill-founded. This ‘paradox of unanimity’ shows that often we are far less certain than we think.”
In response, a friend observed, “A common cause of unanimity is that the prosecution only calls witnesses that help their case and defense is incompetent. The Warren commission comes to mind … ”
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