After a fight outside of a bar, you get arrested by the police. An eyewitness claims that you started the fight by pulling out a knife and threatening someone else. You're facing serious charges.
There's just one problem: The eyewitness is wrong. You were there, but you were simply walking by. You had nothing to do with the crime and just tried to get away from it as quickly as you could. How could they have made such a serious error?