Some fights vanish in plain sight

Bare-knuckled brawlers sometimes have to fight to be seen. College students chasing a person across campus frequently don’t notice two guys beating up a lone victim in plain sight, a new set of experiments finds.

That result has real-world implications, say psychologist Christopher Chabris of Union College in Schenectady, N.Y., and his colleagues. Consider a Boston police officer who was sentenced to prison in 1998 because jurors didn’t believe his claim that, while running after a murder suspect, he passed but didn’t see fellow officers pummeling a misidentified suspect.