The term usually refers to crime subjects, and when the police fires someone else instead of the real culprit. There have been so many such incidents in the past and they admit that it happened due to a 'mistaken identity'.
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Mistaking Thyagu as a real Hitler is mistaken identity boss ...!!!....
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.