John Doe warrant is a warrant for the arrest of a person whose name is unknown. For example, a John Doe warrant can be issued for arrest of a person known by sight but not by name. John Doe warrant can also be used when crime scene evidence yields a DNA profile but the individual corresponding to the DNA profile is unknown. Instead of the suspect's name, the warrant will be filed as "John Doe" and cite the DNA profile. This type of warrant is permitted in a few states, but not in federal practice.