I suppose that is human nature to some degree - "Oh he couldn't possibly be the killer." The example I give a lot of times with a sketch is the Morgan Harrington murder in Charlottesville VA. A year or so later DNA was tied to an attempted rape in Northern VA and there was a sketch of the attacker. When the sketch was circulated in Charlottesville, the employees at a taxi company made jokes about a co-worker, Jesse Matthew, about how he looked like the sketch. No one turned in a tip and Matthew would go on to murder UVA student, Hannah Graham, before he was arrested. BTW, earlier this year LE announced that Jesse Matthew has stage 4 colon cancer. Karma's a real *****, Jesse.