I am prosecuting a case wherein the primary defense is "It wasn't me."
The first witness testifies that he got jumped outside a bar and hit by a drunk guy who had brown hair and was approximately the defendant's size and weight, but the witness did not see the face of his attacker because the witness ran away as soon as somebody came out of the shadows swinging and cussing at him.
Witness number two testifies that, some time before witness one came out of the bar, witness number two came out of the same bar and a drunk guy came out of the shadows cussing at him and tried to hit him, but that he just kept moving and the guy missed him. Witness number two saw the face of his attacker and identifies him as the defendant.
At this point, the case is looking somewhat tenuous as to identification and I'm a little worried. Then the judge asks the witness which bar this happened at. Unbidden, the defendant blurts out, "We were all at Smitty's Bar, Judge."
The case went so much better for the prosecution after that.