This is a science fiction setting initially inspired by the idea of cyborgs, artificial bodies, and making switching a brain between bodies so routine some people do it for recreation.
To make sure people can recognise each other despite switching bodies, everyone has a unique ID taking the shape of a design built into, or applied to, the face of a humanoid body, or an easy to see location for others. There are both laws and strong taboos against obscuring or faking an ID.
Immersive Holiday (previously titled "Identity") is the first published story, playing with the concept a bit.
Identity Theft looks at criminal activity, and has no close relation with the above.
Betrayed from Within is a snapshop of activity in a police station in a crisis