Jane & John Doe - Who?

Often in media and records, people who've been found, but are unable to be identified with IDs on them, witnesses, or composite sketches, are for the purposes of an investigation referred to as Jane Doe, or John Doe.

Crime cases often have "Does", and investigations like these are sadly not uncommon.

But then I started thinking, why on earth do we use the names of "Jane" and "John" "Doe"?

This is what we are going to look at in this week's episode.  

Sources Consulted:

https://docs.google.com/document/d/1DifHinOxK71snkN8Bg_BjVASQhOBc5GDiKTyu2pYNJA/edit?usp=sharing