High Quality Content by WIKIPEDIA articles! Mistaken identity is a defense in criminal law which claims the actual innocence of the criminal defendant, and attempts to undermine evidence of guilt by asserting that any eyewitness to the crime incorrectly thought that they saw the defendant, when in fact the person seen by the witness was someone else. The defendant may question both the memory of the witness (suggesting, for example, that the identification is the result of a false memory), and the perception of the witness (suggesting, for example, that the witness had poor eyesight, or that the crime occurred in a poorly lit place).