John Doe or Jane Doe
A fictitious name used for centuries in the law when a specific person is not known by name.
The name John Doe can be used in a hypothetical situation for the purpose of argument or illustration. For example, the action of EJECTMENT may be used in some states by a person who has possession of a parcel of land but wishes to clear up some doubt concerning his or her right to hold it. Rather than wait until someone else sues to challenge his or her right to the land, that person may bring an action of ejectment against a fictitious defendant, sometimes called a casual ejector. John Doe has traditionally been used for the name of this nonexistent party, but he has also been named Goodtitle.
John Doe may be used for a specific person who is known but cannot be identified by name. The form Jane Doe is often used for anonymous females, and Richard Roe is often used when more than one unknown or fictitious person is named in a lawsuit.
The tradition of fictitious names comes from the Romans, who also had names that they commonly used for fictitious parties in lawsuits. The two names most commonly used were Titius and Seius.