Jane Doe is a generic alias that is used to represent a female in a legal matter. The reason for the use of this alias is typically to intentionally conceal the identity of the woman, or because the woman's true identity is unknown. Jane Doe is sometimes used synonymously with Jane "Roe."
Sometimes, complaints are filed and investigations begin without knowing the actual identity of the defendant. So, occasionally, law enforcement will simply begin to look for, "Jane Doe." It is common to see this and the male counterpart (John Doe) used in real estate cases where any occupant, other than the known occupants, are addressed in the suit. In another example, Jane Doe could be a woman with blonde hair, who stands about five foot tall and who robbed a bank on Friday at around 9:00 am. Jane Doe is just a filler name until law enforcement catches the suspect in this instance. Once the suspect becomes a defendant, her real name will replace Jane Doe.