Then there's the fact that the eyewitness probably didn't know exactly what an actual KKK outfit looks like. Real Klan robes have a distinctive, specific cut to them, and typically a cross emblem on the front. The eyewitness only caught a glimpse of the person, in low light and early in the morning. Psychological studies have shown that under such conditions, the human mind is very poor at accurately perceiving, remembering, and reporting even basic elements of the experience.
Our brains often "fill in" details with what we expect to see –not necessarily what we actually see - and we tend to bias our reports accordingly. Thus a person wrapped in, or even carrying, a light-colored blanket can become a Klan outfit.
Though the sighting remains under investigation and it is possible that a lone hooded Klansman was seen past midnight walking on the Oberlin campus, it seems much more likely that the report was simply an eyewitness error.
Examples like this help remind us that sincere, otherwise credible eyewitnesses can often be influenced by many factors, including what they expect to see. The idea that people often incorrectly see, remember, and report what they experience is not merely theory but a proven fact. There are over 2,000 published scientific studies demonstrating it. By some estimates, as many as 1/3 of eyewitness identifications in criminal cases are wrong, and nearly 200 people who were convicted of crimes based on positive eyewitness identifications were later exonerated through DNA evidence.